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FEATURES
Quad Outputs, Dual 12A and Dual 5A, Step-Down
n
μModule
Regulator with Digital Interface
®
Wide Input Voltage Range: 4.5V to 15V
n
Dual 12A DC Output From 0.6V to 3.3V
n
Dual 5A DC Output From 0.6V to 5.5V
n
±0.5% Total Output Voltage Regulation with Servo
n
±5% Current Readback Accuracy in 12A Channels
n
400kHz PMBus-Compliant I
n
Integrated 16-Bit ΔΣ ADC
n
Accurate Monitoring Input and Four Output Voltages,
n
Currents, and Temperatures
Digital Programmable Output Voltage Trim,
n
Sequencing and Margining for Each Channel
Manage Faults and Warnings
n
Onboard EEPROM Fault Log Record
n
Dual True Differential Sensing Amplifier
n
Parallelable Output for Higher Output Current
n
Drop-In Pin Compatible with Quad Output LTM4671
n
Non-PSM μModule Regulator
16mm × 16mm × 4.72mm BGA Package
n
APPLICATIONS
Telecom, Networking and Industrial Equipment
n
Multi-Rail Point of Load Regulation
n
FPGAs, DSPs and ASICs Application
n
TYPICAL APPLICATION
Dual 12A, Dual 5A Output DC/DC µModule Regulator with Digital Power System Management
4.5V TO 15V
V
OUT3
0.9V/12A
100 F
787k
121k
V
OUT2
1.8V/5A
47 F
402k
30.1k
2
I
C/SMBus I/F WITH PMBus
COMMAND SET TO/FROM
IPMI OR OTHER BOARD
MANAGEMENT CONTROLLER
Document Feedback
Quad Output μModule Regulator with
Digital Power System Management
2
C Serial Interface
R
SENSE
100 F
×2
V
OUT3
+
V
OSNS3
–
V
OSNS3
V
DAC3
FB3
LTM4673
V
OUT2
+
V
OSNS2
–
V
OSNS2
V
DAC2
FB2
ON/OFF
SYNCHRONIZATION
CONTROL
TIME-BASE
REGISTER WRITE
PROTECTION
For more information
DESCRIPTION
The
LTM
4673
®
switching mode DC/DC step-down μModule (powermodule)
regulator integrated with 4-channel Power System Manager
used to sequence, trim (servo), margin, supervise, manage
faults, provide telemetry, and create fault logs. Operating
over an input voltage range of 4.5V to 15V, the LTM4673
supports an output voltage range of 0.6V to 3.3V for 12A
channels and 0.6V to 5.5V for 5A channels. Only bulk input
and output capacitors are needed.
The LTM4673's 2-wire serial interface allows outputs
to be precisely margined, tuned and programmable
sequenced up and down. An internal 16-bit ADC monitors
and supervises input and all four output voltages, currents
and temperatures. Faults can be programmed for
overcurrent and undercurrent, voltage and temperature
threshold limits for four output channels as well as over
and undervoltage for the input.
The LTM4673 is offered in a 16mm × 16mm × 4.72mm
BGA package with RoHS compliant terminal finish.
Configurable Output Array
12A
12A
5A
5A
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. patents, including 5481178, 5847554, 6580258, 6304066, 6476589, 6774611,
7382303, 7420359 and 8648623.
22 F
×4
V
V
OUT0
OUT0
1.0V/12A
+
V
OSNS0
100 F
–
V
OSNS0
715k
V
DAC0
90.9k
FB0
V
OUT1
V
OUT1
1.2V/5A
+
V
OSNS1
47 F
–
V
OSNS1
590k
V
DAC1
60.4k
FB1
4673 TA01a
www.analog.com
LTM4673
is a quad output, dual 12A and dual 5A,
12A
24A
24A
12A
5A
10A
10A
5A
Efficiency vs Load Current,
12V Input
90
88
86
84
82
80
78
76
74
72
70
0
2
4
6
LOAD CURRENT (A)
V
= 1.8V
OUT2
V
= 1.2V
OUT1
V
= 1.0V
OUT0
V
= 0.9V
OUT3
8
10
12
4673 TA01b
Rev. 0
1
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Table of Contents
Related Manuals for Linear Analog Devices LTM4673
Summary of Contents for Linear Analog Devices LTM4673
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Page 1: Features
LTM4673 Quad Output μModule Regulator with Digital Power System Management FEATURES DESCRIPTION Quad Outputs, Dual 12A and Dual 5A, Step-Down 4673 is a quad output, dual 12A and dual 5A, ® switching mode DC/DC step-down μModule (powermodule) μModule Regulator with Digital Interface ®... -
Page 2: Table Of Contents
LTM4673 TABLE OF CONTENTS Features ..............1 Output Overvoltage, Undervoltage, Overcurrent and Applications ..............1 Undercurrent Faults ............43 Typical Application ............1 Output Overvoltage, Undervoltage, and Overcurrent Description..............1 Warnings ................43 Absolute Maximum Ratings ..........4 Configuring the AUXFAULT Output ........44 Pin Configuration ............5 Multichannel Parallel Operation ..........44 Order Information ............5 Input RMS Ripple Current Cancellation ........44 Electrical Characteristics ..........6... - Page 3 LTM4673 TABLE OF CONTENTS Input Voltage Commands and Limits ........81 CLEAR_FAULTS ..............99 VIN_ON, VIN_OFF, VIN_OV_FAULT_LIMIT, VIN_OV_WARN_ STATUS_BYTE..............100 LIMIT, VIN_UV_WARN_LIMIT and STATUS_WORD ..............100 VIN_UV_FAULT_LIMIT ............81 STATUS_VOUT ..............101 INPUT Current and ENERGY ............82 STATUS_IOUT ..............101 Energy Measurement and Reporting ........82 STATUS_INPUT ..............101 MFR_EIN ................83 STATUS_TEMPERATURE ..........102 MFR_EIN_CONFIG .............83...
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Page 4: Absolute Maximum Ratings
LTM4673 ABSOLUTE MAXIMUM RATINGS (Note 1) , SV , SV ........–0.3V to 15V Digital Supply Voltages: ..........–0.3V to 3.6V ............–0.3V to 15V OUT0 OUT3 IN_D ..........–0.3V to 6V ............ –0.3V to 3.6V OUT1 OUT2 DD33 INTV , INTV , INTV .... -
Page 5: Pin Configuration
LTM4673 PIN CONFIGURATION TOP VIEW – TSENSE0 TSENSE0 OUT0 SGND INTV PMODE0 CLKOUT0 PWRGD0 TRACK/ – FREQ0 RUN0 ALERTB FAULT1 CTRL3 SHARECLK PWRGD OSNS0 TRACK/ MODE/ WDI/ CLKIN0 CTRL0 CTRL1 FAULT0 CTRL2 RESET OSNS0 PWRGD1 COMP0a COMP0b ASEL0 TSENSE2 IN_D DD25 –... -
Page 6: Electrical Characteristics
LTM4673 ELECTRICAL CHARACTERISTICS denotes the specifications which apply over the specified internal operating temperature range. Specified as each individual output channel. T = 25°C (Note 2), SV = 12V, unless otherwise noted. Per the typical application in Figure 53. SYMBOL PARAMETER CONDITIONS UNITS Switching Regulator Section: (12A Channels) - Page 7 LTM4673 ELECTRICAL CHARACTERISTICS denotes the specifications which apply over the specified internal operating temperature range. Specified as each individual output channel. T = 25°C (Note 2), SV = 12V, unless otherwise noted. Per the typical application in Figure 53. SYMBOL PARAMETER CONDITIONS UNITS Switching Regulator Section: (5A Channels)
- Page 8 LTM4673 ELECTRICAL CHARACTERISTICS denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25°C (Note 2). V = 12V, V pins floating, unless IN_D INSNS DD33 DD25 otherwise indicated. SYMBOL PARAMETER CONDITIONS UNITS Digital Power Supply Characteristics Supply Input Operating Range V Floating (Note 17)
- Page 9 LTM4673 ELECTRICAL CHARACTERISTICS denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25°C (Note 2). V = 12V, V pins floating, unless IN_D INSNS DD33 DD25 otherwise indicated. SYMBOL PARAMETER CONDITIONS UNITS Current Supervisor Characteristics (Note 17) Current Sense Range (Note 17) Differential Voltage...
- Page 10 LTM4673 ELECTRICAL CHARACTERISTICS denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25°C (Note 2). V = 12V, V pins floating, unless otherwise IN_D DD33 DD25 indicated. SYMBOL PARAMETER CONDITIONS UNITS Conversion Time (Note 4) CONV_IIN Update Rate (Note 4) UPDATE...
- Page 11 LTM4673 ELECTRICAL CHARACTERISTICS denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25°C (Note 2). V = 12V, V pins floating, unless otherwise IN_D DD33 DD25 indicated. SYMBOL PARAMETER CONDITIONS UNITS Watchdog Timer Interrupt Input Frequency Input Capacitance Digital Input SHARECLK (Note 17)
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Page 12: Pmbus Timing Diagram
LTM4673 ELECTRICAL CHARACTERISTICS Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 7: The LTM4673 will not acknowledge any PMBus commands, may cause permanent damage to the device. Exposure to any Absolute except for MFR_COMMON, when a STORE_USER_ALL command is being Maximum Rating condition for extended periods may affect device executed. -
Page 13: Typical Performance Characteristics
LTM4673 TYPICAL PERFORMANCE CHARACTERISTICS Dual 12A Channels Efficiency vs Load Current Efficiency vs Load Current from 5V from 12V = 3.3V = 2.5V = 3.3V = 2.5V = 1.8V = 1.8V = 1.5V = 1.5V = 1.2V = 1.2V = 1.0V = 1.0V = 0.9V = 0.9V LOAD CURRENT (A) - Page 14 LTM4673 TYPICAL PERFORMANCE CHARACTERISTICS Dual 12A Channels Short-Circuit Waveform with Start-Up Waveform with No Load Start-Up Waveform with 12A Load No Load Current Exist, V Current Applied Current Applied Undervoltage Fault Response 20V/DIV 20V/DIV PWRGD PWRGD 1A/DIV 5V/DIV 5V/DIV 500mA/DIV 1A/DIV 1V/DIV 1V/DIV...
- Page 15 LTM4673 TYPICAL PERFORMANCE CHARACTERISTICS Dual 5A Channels Efficiency vs Load Current Efficiency vs Load Current from 5V from 12V = 3.3V = 2.5V = 1.8V = 5.0V = 1.5V = 1.5V = 3.3V = 1.2V = 1.2V = 2.5V = 1.0V = 1.0V = 1.8V = 0.9V = 0.9V...
- Page 16 LTM4673 TYPICAL PERFORMANCE CHARACTERISTICS Dual 5A Channels Start-Up Waveform with No Load Start-Up Waveform with 5A Load 5V Output Transient Response Current Applied Current Applied 10V/DIV 10V/DIV PWRGD PWRGD (AC-COUPLED) 5V/DIV 5V/DIV 100mV/DIV 200mA/DIV 200mA/DIV LOAD STEP 1A/DIV 1V/DIV 1V/DIV 4673 G26 4673 G27 50 s/DIV...
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Page 17: Pin Functions
LTM4673 TYPICAL PERFORMANCE CHARACTERISTICS READ_IOUT of 10 LTM4673 READ_IOUT of 10 LTM4673 READ_IOUT of 10 LTM4673 Channels (DC2810A) Channels (DC2810A) Channels (DC2810A) 4.95 4.99 5.03 5.07 5.11 5.15 5.19 4.64 4.76 4.87 4.98 5.10 5.21 5.33 4.99 5.02 5.05 5.07 5.10 5.13 5.16... - Page 18 LTM4673 PIN FUNCTIONS INTV (Pin E7), INTV (Pin R11): Internal 3.3V external resistor can be placed from this pin to GND to Regulator Output of Each 12A Switching Mode Regulator increase frequency, or from this pin to INTV to reduce Channel.
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Page 19: Pins For Dual 5A Channels
LTM4673 PIN FUNCTIONS COMP0b (Pin H11), COMP3b (Pin N8): Internal Loop (Pin J10), V (Pin L10): Positive Output OSNS1 OSNS2 Compensation Network for Each 12A Switching Mode Voltage Sense Pin of Each 5A Switching Mode Regulator Regulator Channel. Connect to COMP0a or COMP3a, Channel. -
Page 20: Pins For Digital Power System Management
LTM4673 PIN FUNCTIONS phase-locked loop will force the channel 1 turn on signal (Pins G19, H19): 2.5V Internally Regulated Voltage DD25 to be synchronized with the rising edge of the CLKIN12 Output. Do not connect to V pins of any other devices. DD25 signal. -
Page 21: Block Diagram
LTM4673 BLOCK DIAGRAM MODE/ CLKIN0 SAME BLOCK FOR CHANNEL 3 100k PWRGD0 INTV CLKOUT0 INTV 0.1 F OUT0 0.3 H 1.0V/12A 2.2 F 2.2 F OUT0 TRACK/SS0 0.1 F 100 F COMP0a 0.1 F POWER – 150pF OSNS0 CONTROL COMP0b 18pF INTERNAL 121k... -
Page 22: Decoupling Requirements
LTM4673 DECOUPLING REQUIREMENTS SYMBOL PARAMETER CONDITIONS UNITS External Input Capacitor Requirement µF = 4.5V to 15V, V = 1.5V) External Output Capacitor Requirement = 12A µF OUT0 OUT3 = 4.5V to 15V, V = 1.5V) External Output Capacitor Requirement = 5A µF OUT1 OUT2... - Page 23 LTM4673 OPERATION The LTM4673 has integrated power system manager • Supervise an external microcontroller’s activity for a LTC2975 inside the module. Features of the LTM4673 stalled condition with a programmable watchdog timer that enable power system management, rail sequening and reset it if necessary. and fault monitering and reporting are as follows: •...
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Page 24: Eeprom
LTM4673 OPERATION EEPROM So the overall retention of the EEPROM was degraded by 86.5 hours as a result of operation at a junction The LTM4673 contains internal EEPROM (Nonvolatile temperature of 145°C for 10 hours. Note that the effect Memory) to store configuration settings and fault log of this overstress is negligible when compared to the information. -
Page 25: Reset
LTM4673 OPERATION RESET The PMBus two wire interface is an incremental exten- sion of the SMBus. SMBus is built upon I C with some Holding the WDI/RESET pin low for more than t will RESET minor differences in timing, DC parameters and protocol. cause the LTM4673 to enter the power-on reset state. -
Page 26: Processing Commands
LTM4673 OPERATION Processing Commands The LTM4673 uses a dedicated processing block to command. These are summarized in the following tables. ensure quick response to all of its commands. There are MFR_COMMON is a special command that may always be a few exceptions where the part will NACK a subsequent read even when the part is busy. - Page 27 LTM4673 OPERATION Table 1. LTM4673 Address Look-Up Table with MFR_I2C_BASE_ADDRESS Set to 7-Bit 0x5C ADDRESS PINS HEX DEVICE ADDRESS BINARY DEVICE ADDRESS ASEL1 ASEL0 DESCRIPTION 7-Bit 8-Bit Alert Response Global N = 0 N = 1 N = 2 N = 3 N = 4 N = 5 N = 6...
- Page 28 LTM4673 OPERATION SLAVE ADDRESS Wr A COMMAND CODE DATA BYTE LOW DATA BYTE HIGH 4673 F06 Figure 6. Write Word Protocol with PEC SLAVE ADDRESS Wr A COMMAND CODE 4673 F07 Figure 7. Send Byte Protocol SLAVE ADDRESS Wr A COMMAND CODE 4673 F08 Figure 8.
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Page 29: Pmbus Command Summary
LTM4673 PMBus COMMAND SUMMARY Summary Table DATA DEFAULT VALUE: COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM FLOAT HEX PAGE PAGE 0x00 Channel or page currently selected for R/W Byte 0x00 any command that supports paging. OPERATION 0x01 Operating mode control. On/Off, R/W Byte 0x80 Margin High and Margin Low. - Page 30 LTM4673 PMBus COMMAND SUMMARY Summary Table DATA DEFAULT VALUE: COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM FLOAT HEX PAGE VOUT_OV_FAULT_RESPONSE 0x41 Action to be taken by the device when R/W Byte 0x80 an output overvoltage fault is detected. VOUT_OV_WARN_LIMIT 0x42 Output overvoltage warning limit.
- Page 31 LTM4673 PMBus COMMAND SUMMARY Summary Table DATA DEFAULT VALUE: COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM FLOAT HEX PAGE VIN_OV_WARN_LIMIT 0x57 Input overvoltage warning limit R/W Word 14.0 0xD380 measured at VINSNS pin. VIN_UV_WARN_LIMIT 0x58 Input undervoltage warning limit R/W Word 0 0x8000 measured at VINSNS pin.
- Page 32 LTM4673 PMBus COMMAND SUMMARY Summary Table DATA DEFAULT VALUE: COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM FLOAT HEX PAGE READ_TEMPERATURE_1 0x8D Power stage temperature sensor. This is R Word °C the value used for all temperature related processing, including IOUT_CAL_GAIN. READ_TEMPERATURE_2 0x8E Control IC die temperature.
- Page 33 LTM4673 PMBus COMMAND SUMMARY Summary Table DATA DEFAULT VALUE: COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM FLOAT HEX PAGE MFR_COMMAND_PLUS 0xC8 Alternate access to block read and other R/W Word data. Commands for all additional hosts. MFR_DATA_PLUS0 0xC9 Alternate access to block read and R/W Word other data.
- Page 34 LTM4673 PMBus COMMAND SUMMARY Summary Table DATA DEFAULT VALUE: COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM FLOAT HEX PAGE MFR_PAGE_FF_MASK 0xE4 Configuration defining which channels R/W Byte 0x0F respond to global page commands (PAGE=0xFF). MFR_PADS 0xE5 Current state of selected digital I/O pads. R/W Word MFR_I2C_BASE_ADDRESS 0xE6 Base value of the I C/SMBus address...
- Page 35 LTM4673 PMBus COMMAND SUMMARY Data Formats Linear_5s_11s PMBus data field b[15:0] Value = Y • 2 where N = b[15:11] is a 5-bit two’s complement integer and Y = b[10:0] is an 11-bit two’s complement integer Example: READ_VIN = 10V For b[15:0] = 0xD280 = 1101_0010_1000_0000b –6 Value = 640 •...
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Page 36: Applications Information
4.5V and 15V be applied the minimum on-time limit imposes a minimum duty cycle to the V pin. See Figure 15. An internal linear regulator IN_D of the converter which can be calculated with Equation 3. -
Page 37: Output Voltage Programming And Trimming
LTM4673 APPLICATIONS INFORMATION input source impedance is compromised by long induc- OUTPUT DECOUPLING CAPACITORS tive leads, traces or not enough source capacitance. The With an optimized high frequency, high bandwidth design, bulk capacitor can be an electrolytic aluminum capacitor only single piece of low ESR output ceramic capacitor is and polymer capacitor. -
Page 38: Operating Frequency
LTM4673 APPLICATIONS INFORMATION For the 12A channels (CH0, CH3), discontinuous mode The programmable operating frequency range for chan- (DCM) can be achieved by tying the MODE/CLKIN0 or nels 0 and 3 is from 400kHz to 3MHz. MODE/CLKIN3 pin to GND. In discontinuous mode, the For the 5A channels (CH1, CH2), If an operating fre- reverse current comparator will sense the inductor current quency other than 1MHz is required by the application,... -
Page 39: Soft-Start
LTM4673 APPLICATIONS INFORMATION SOFT-START reduction, an additional 10pF to 15pF phase boost cap ) is required between V and FB pins. The TRACK/SS pin provides a means to either soft-start of each regulator channel or track it to a different power For specific optimized requirement for the dual 12A chan- supply. -
Page 40: Measuring Input Voltage
LTM4673 APPLICATIONS INFORMATION may be set to zero. Otherwise, choose a setting for the MFR_IIN_CAL_GAIN_TC value in units of ppm/°C to cor- rect for R thermal drift. SENSE For best results, it is recommended to locate R close HIGH RANGE SENSE to and isothermal with the LTM4673. -
Page 41: Measuring Input Energy
LTM4673 APPLICATIONS INFORMATION For example, if 15mV < |V | < 50mV with the cur- SEQUENCE, SERVO, MARGIN AND RESTART IINSNS rent sense amplifier set for medium range, TUE_IIN ≤ OPERATIONS 1% and TUE_PIN is less than 1% (TUE_IIN) + 0.5% Command Units On or Off (TUE_VIN) = 1.5%. -
Page 42: On State Operation
LTM4673 APPLICATIONS INFORMATION As part of continuous/noncontinuous trim mode, fast servo mode can be used to speed up large output transi- CONTROL tions, such as margin commands, or ON events. To use, set Mfr_config_fast_servo_off = 0. When enabled, fast servo is started by a change to the target voltage or a new VOUT_OV_FAULT_LIMIT softconnect. -
Page 43: Off Sequencing
LTM4673 APPLICATIONS INFORMATION Margining is actuated by writing the appropriate bits to CONTROL PIN BOUNCE the OPERATION register. CONTROL Margining requires the DAC to be connected. Margin requests that occur when the DAC is disconnected will RUN0 be ignored. 4673 F22 TOFF_DELAY0 MFR_RESTART_DELAY TON_DELAY0... -
Page 44: Configuring The Auxfault Output
LTM4673 APPLICATIONS INFORMATION IOUT_OC_WARN_LIMIT commands, respectively. Note A multiphase power supply significantly reduces the that there is no I UC warning threshold. If a warning amount of ripple current in both the input and output occurs, the corresponding bits are set in the status reg- capacitors. -
Page 45: Output Voltage Tracking
LTM4673 APPLICATIONS INFORMATION 0.60 1-PHASE 2-PHASE 0.55 FAULT0 CONTROL0 3-PHASE 4-PHASE OUT0 OUT0 6-PHASE 0.50 220µF OSNS0 RECOMMENDED – CONNECTION WHEN OSNS0 0.45 HARDWARE ON/OFF PWRGD0 CONTROL IS REQUIRED CONTROL1 0.40 OUT1 OUT1 47µF 0.35 OSNS1 – OSNS1 0.30 LTM4673 PWRGD1 CONTROL2 0.25... - Page 46 LTM4673 APPLICATIONS INFORMATION TOFF_DELAY3 TOFF_DELAY2 TOFF_DELAY1 TOFF_DELAY0 OUT0 OUT1 OUT2 OUT3 CONTROL-FAULT0 PWRGD0 PWRGD1 PWRGD2 PWRGD3 4673 F26 Figure 26. Cascade Sequence ON with Time Based Sequence Down on FAULT0 OUT2: 1.8V/5A OUT2 30.2k 47µF LTM4673 0.1µF TRACK/SS2 TR1(TOP) 60.4k FAULT0 OUT1: 1.2V/5A OUT1 47µF...
- Page 47 LTM4673 APPLICATIONS INFORMATION monitoring the slaves to disable UV detection. Slave UC • Ignore UV and UC during TOFF_DELAY. Note that detection must also be disabled when the slaves are ignoring UV and UC during TON_RISE and TON_MAX_ tracking the master down to prevent false UC events. All FAULT always happens regardless of how this bit is set.
- Page 48 LTM4673 APPLICATIONS INFORMATION TON_RISE EXPIRES TOFF_DELAY ENTERED FOR ALL CHANNELS. FOR ALL CHANNELS. UV AND UC DETECT ENABLED UV AND UC DETECT DISABLED ON ALL CHANNELS ON ALL CHANNELS OUT2 OUT1 OUT0 MASTER BRINGS DOWN NEXT HIGHEST SLAVE OUT3 CONTROL RUN2 RUN0,1,3 4673 F28...
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Page 49: Multi-Channel Fault Management
LTM4673 APPLICATIONS INFORMATION TON_RISE EXPIRES TOFF_DELAY ENTERED FOR ALL CHANNELS. FOR ALL CHANNELS. UV AND UC DETECT ENABLED UV AND UC DETECT DISABLED ON ALL CHANNELS ON ALL CHANNELS UV FAULT ON CHANNEL 1 BRINGS DOWN MASTER OUT2 VIA FAULT0. ALL SLAVES WITH ENABLED RUN OUT1 PINS TRACK DOWN CORRECTLY OUT0... -
Page 50: Interconnect Between Multiple Analog Devices Power Managers
LTM4673 APPLICATIONS INFORMATION Mfr_faultb0_response, page = 0 Mfr_faultb0_propagate_chan0 FAULTED_OFF CHANNEL 0 FAULT0 Mfr_faultb1_response, page = 0 Mfr_faultb1_propagate_chan0 EVENT PROCESSOR PAGE = 0 Mfr_faultb0_response, page = 1 Mfr_faultb0_propagate_chan1 FAULTED_OFF CHANNEL 1 Mfr_faultb1_response, page = 1 Mfr_faultb1_propagate_chan1 EVENT PROCESSOR PAGE = 1 Mfr_faultb0_response, page = 2 Mfr_faultb0_propagate_chan2 FAULT1... - Page 51 LTM4673 APPLICATIONS INFORMATION TO V TO INPUT TO HOST CONTROLLER DC/DCs SWITCH LTM4673 #1 LTM4673 #n VINSNS VINSNS FAULT AUXFAULT ALERT ALERT CONTROL0 CONTROL0 WDI/RESET WDI/RESET FAULT0 FAULT0 SHARECLK SHARECLK PWRGD PWRGD 4673 F32 TO OTHER ADI POWER SYSTEM MANAGERS–10k EQUIVALENT PULL-UP RECOMMENDED ON EACH LINE EXCEPT SHARE_CLK (USE 5.49k) Figure 32.
- Page 52 LTM4673 APPLICATIONS INFORMATION Figure 34 shows the recommended schematic to use be powered from the ORed 3.3V supply. In addition, when the LTM4673 is powered by the system intermedi- any device sharing I C/SMBus bus connections with the ate bus through its V pin.
-
Page 53: Ltpowerplay: An Interactive Gui For Power Managers
You can software tool can be used to calculate R values. use LTpowerPlay to evaluate Linear Technology ICs by 1. Determine the bottom V resistor value. connecting to a demo board system. LTpowerPlay can... - Page 54 LTM4673 APPLICATIONS INFORMATION Figure 36. LTpowerPlay Snapshot 2. Solve for the value of R that yields the maximum For Channel 0, V is 1.0V, set V at 0.95V, VDAC DC(NOM) DC(MIN) required DC/DC converter output voltage V = 0.6V, V should not be greater than 1.4V. DC(MAX) FS_VDAC0 Set V...
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Page 55: Thermal Considerations And Output Current Derating
LTM4673 APPLICATIONS INFORMATION maximum output voltage can be calculated as follows: 2. θ , the thermal resistance from junction to the JCbottom = 1.0V, V = 0.95V, V = 1.05V. bottom of the product, is determined with all of the DC(NOM) DC(MIN) DC(MAX) - Page 56 Pin Configuration section and should accurately equal exactly linear with respect to total package power loss. To the θ value because approximately 100% of power loss...
- Page 57 LTM4673 APPLICATIONS INFORMATION = 3.3V = 3.3V = 2.5V = 2.5V = 1.8V = 1.8V = 1.5V = 1.5V = 1.2V = 1.2V = 1.0V = 1.0V LOAD CURRENT (A) LOAD CURRENT (A) LOAD CURRENT (A) 4673 F38 4673 F39 4673 F40 Figure 38.
- Page 58 LTM4673 APPLICATIONS INFORMATION Thermal Derating Thermal Derating Thermal Derating 0LFM 0LFM 0LFM 200LFM 200LFM 200LFM 400LFM 400LFM 400LFM CH0, CH3 PARALLELED TO 1.8V/24A CH0, CH3 PARALLELED TO 1.8V/24A CH0, CH3 PARALLELED TO 1.8V/24A CH1, CH2 PARALLELED TO 3.3V/10A CH1, CH2 PARALLELED TO 3.3V/10A CH1, CH2 PARALLELED TO 3.3V/10A (°C) (°C)
- Page 59 LTM4673 APPLICATIONS INFORMATION ambient temperature. The decreased output current will through Table 5 for the various conditions can be multi- decrease the internal module loss as ambient tempera- plied by the calculated power loss as a function of ambient ture is increased. The monitored junction temperature of temperature to derive temperature rise above ambient, 120°C minus the ambient operating temperature specifies thus maximum junction temperature.
- Page 60 LTM4673 APPLICATIONS INFORMATION Table 4. V = 1.8V, V = 3.3V OUT0 OUT3 OUT1 OUT2 DERATING CURVE (V) POWER LOSS CURVE AIRFLOW (LFM) HEAT SINK θ JA(°C/W) Figure 46, Figure 47 5, 12 Figure 38, Figure 39, Figure 40, Figure 41 None Figure 46, Figure 47 5, 12 Figure 38, Figure 39, Figure 40, Figure 41 None Figure 46, Figure 47 5, 12...
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Page 61: Safety Considerations
LTM4673 APPLICATIONS INFORMATION Table 6. Output Voltage Response vs Component Matrix (Refer to Figure 53) 0 to 25% Load Step Typical Measured Values (CERAMIC) (CERAMIC) (BULK) VENDOR VALUE PART NUMBER VENDOR VALUE PART NUMBER VENDOR VALUE PART NUMBER Murata 22uF , X5R, GRM31CR61E226KE15L Murata 100uF ,... - Page 62 LTM4673 APPLICATIONS INFORMATION • For parallel modules, tie the V , and COMP pins • Place high frequency ceramic input and output capaci- together. Use an internal layer to closely connect these tors next to the V , GND and V pins to minimize pins together.
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Page 63: Typical Applications
LTM4673 TYPICAL APPLICATIONS 5mΩ 4.5V TO 15V OUT0 OUT0 100 F 22 F 1.0V, 12A ×2 150pF ×4 INSNS OSNS0 100 F 787k ×2 SVIN3 DAC0 90.9k SVIN0 – INSNSM OSNS0 INSNSP OUT1 OUT1 1.2V, 5A 22pF 47 F OSNS1 590k ×2 CONTROL0... - Page 64 LTM4673 TYPICAL APPLICATIONS OUT0 OUT0 5mΩ 1.0V, 24A OUT3 4.5V TO 15V 150pF SVIN0 22 F 100 F 100 F ×2 OSNS0 ×4 ×2 ×4 SVIN3 OSNS3 715k DAC0 INSNS 90.9k INSNSM – INSNSP OSNS0 – OSNS3 CONTROL0 CONTROL1 ON/OFF CONTROL CONTROL2 OUT1 OUT1...
- Page 65 LTM4673 TYPICAL APPLICATIONS OUT0 OUT0 1.0V, 24A 5mΩ OUT3 150pF OSNS0 ×2 4.5V TO 15V OSNS3 715k SVIN0 22 F 100 F 100 F ×4 DAC0 ×2 ×4 SVIN3 DAC3 90.9k INSNS – OSNS0 INSNSM – OSNS3 INSNSP CONTROL0 OUT1 OUT1 CONTROL1 1.2V, 5A...
- Page 66 LTM4673 TYPICAL APPLICATIONS OUT0 OUT0 5mΩ 0.9V, 12A 150pF 4.5V TO 15V OSNS0 787k 2x100uF SVIN0 22 F 100 F DAC0 121k ×4 ×2 SVIN3 – OSNS0 INSNS OUT1 OUT1 3.3V, 10A OUT2 INSNSM 22pF INSNSP ×2 47 F OSNS1 ×4 OSNS2 590k...
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Page 67: Pmbus Command Description
LTM4673 PMBus COMMAND DESCRIPTION ADDRESSING AND WRITE PROTECT DEFAULT COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM VALUE PAGE PAGE 0x00 Channel or page currently selected for any R/W Byte 0x00 command that supports paging. WRITE_PROTECT 0x10 Level of protection provided by the device R/W Byte 0x00 against accidental changes. -
Page 68: Write_Protect
LTM4673 PMBus COMMAND DESCRIPTION WRITE_PROTECT The WRITE_PROTECT command provides protection against accidental programming of the LTM4673 command registers. All supported commands may have their parameters read, regardless of the WRITE_PROTECT setting, and the EEPROM contents can also be read regardless of the WRITE_PROTECT settings. There are two levels of protection: •... -
Page 69: Mfr_I2C_Base_Address
LTM4673 PMBus COMMAND DESCRIPTION MFR_PAGE_FF_MASK Data Contents BIT(S) SYMBOL OPERATION b[0] Mfr_page_ff_mask_chan0 Channel 0 masking of global page command (PAGE = 0xFF) accesses 0 = ignore global page command accesses 1 = fully respond to global page command accesses MFR_I2C_BASE_ADDRESS The MFR_I2C_BASE_ADDRESS command determines the base value for the I C/SMBus address byte. -
Page 70: Plus0
LTM4673 PMBus COMMAND DESCRIPTION MFR_COMMAND_PLUS Data Contents b[13:9] Mfr_command_plus_page Page to be used when peeking or poking via Mfr_data_plus0 or Mfr_data_plus1. Allowed values are 0 through 3. This page value is cached separately for Mfr_data_plus0 and Mfr_data_plus1 based on the value of Mfr_command_plus_id when this register is written. -
Page 71: Data_Plus0
LTM4673 PMBus COMMAND DESCRIPTION Check status to be sure the data just read was all valid: • Write Mfr_command_plus_pointer = 0x2C with Mfr_command_plus_page = 0 and Mfr_command_plus_id = 0. • Read data from Mfr_data_plus0 and confirm that Mfr_status_plus_block_peek_failed0 = 0. Reading Energy Using MFR_COMMAND_PLUS and MFR_DATA_PLUS0 Write Mfr_command_plus_pointer = 0xC0 with Mfr_command_plus_page = 0 and Mfr_command_plus_id = 0. -
Page 72: Command Plus Operations Using Mfr_Data_Plus1
LTM4673 PMBus COMMAND DESCRIPTION • Read data from Mfr_data_plus0 and confirm that Mfr_status_plus_poke_failed0 = 0. Command Plus Operations Using Mfr_data_plus1 All the previous operations may be accessed via Mfr_data_plus1 by substituting Mfr_command_plus_id value with a 1. Poke operations must be enabled for Mfr_data_plus1. ON/OFF CONTROL, MARGINING AND CONFIGURATION DEFAULT COMMAND NAME... -
Page 73: On_Off_Config
LTM4673 PMBus COMMAND DESCRIPTION OPERATION Data Contents (On_off_config_use_pmbus = 0) On or Off OPERATION_ OPERATION_ OPERATION_ RESERVED SYMBOL CONTROL[1:0] MARGIN[1:0] FAULT[1:0] (READ ONLY) BITS ACTION b[7:6] b[5:4] b[3:2] b[1:0] Output at nominal 00, 01 or 10 Margin low (ignore faults and 00, 01 or 10 warnings) Margin low... -
Page 74: Mfr_Config_Ltm4673
LTM4673 PMBus COMMAND DESCRIPTION MFR_CONFIG_LTM4673 This command is used to configure various manufacturer specific operating parameters for each channel. MFR_CONFIG_LTM4673 Data Contents BIT(S) SYMBOL OPERATION b[15] Reserved Don’t care. Always returns 0. b[14] Mfr_config_cascade_on Configures channel’s control pin for cascade sequence ON. There is no provision for cascade sequence OFF . -
Page 75: Mfr_Config2_Ltm4673
LTM4673 PMBus COMMAND DESCRIPTION MFR_CONFIG_LTM4673 Data Contents BIT(S) SYMBOL OPERATION b[1] Mfr_config_dac_gain DAC buffer gain. 0: Select DAC buffer gain dac_gain_0 (1.38V full-scale) 1: Select DAC buffer gain dac_gain_1 (2.65V full-scale) b[0] Mfr_config_ dac_pol DAC output polarity. 0: Encodes negative (inverting) DC/DC converter trim input. 1: Encodes positive (non-inverting) DC/DC converter trim input. -
Page 76: Mfr_Config3_Ltm4673
LTM4673 PMBus COMMAND DESCRIPTION MFR_CONFIG3_LTM4673 This command register determines whether V undercurrent faults from a given channel cause the AUXFAULT pin to be pulled low. This command also allows tracking to be enabled on any channel. MFR_CONFIG3_LTM4673 Data Contents BIT(S) SYMBOL OPERATION b[7] Mfr_auxfaultb_uc_fault_response_... -
Page 77: Mfr_Config_All_Ltm4673
LTM4673 PMBus COMMAND DESCRIPTION MFR_CONFIG_ALL_LTM4673 This command is used to configure parameters that are common to all channels on the IC. They may be set or reviewed from any PAGE setting. MFR_CONFIG_ALL_LTM4673 Data Contents BIT(S) SYMBOL OPERATION b[15:12] Reserved Don’t care. Always returns 0. b[11] Mfr_config_all_pwrgd_off_uses_uv Selects PWRGD de-assertion source for all channels. -
Page 78: Programming User Eeprom Space
LTM4673 PMBus COMMAND DESCRIPTION MFR_CONFIG_ALL_LTM4673 Data Contents BIT(S) SYMBOL OPERATION b[4] Mfr_config_all_control0_pol Selects active polarity of CONTROL0 pin 0: Active low (pull pin low to start unit). 1: Active high (pull pin high to start unit). b[3] Mfr_config_all_vin_share_enable Allow this unit to hold Share-clock pin low when V has not risen above VIN_ON or has fallen below VIN_OFF. -
Page 79: Store_User_All And Restore_User_All
LTM4673 PMBus COMMAND DESCRIPTION STORE_USER_ALL and RESTORE_USER_ALL STORE_USER_ALL, RESTORE_USER_ALL commands provide access to User EEPROM space. Once a command is stored in User EEPROM, it will be restored with explicit restore command, when the part emerges from power-on reset after power is applied, or after toggling the Reset pin. While either of these commands is being processed, the part will indicate it is busy, see Response When Part Is Busy on page 81. -
Page 80: Mfr_Ee_Erase
LTM4673 PMBus COMMAND DESCRIPTION MFR_EE_UNLOCK Data Contents BIT(S) SYMBOL OPERATION b[7:0] Mfr_ee_unlock[7:0] To unlock user EEPROM space for Mfr_ee_erase and Mfr_ee_data read or write operations with PEC allowed: Write 0x2b followed by 0xd4. To unlock user EEPROM space for Mfr_ee_erase and Mfr_ee_data read or write operations with PEC required: Write 0x2b followed by 0xd5. -
Page 81: Response When Part Is Busy
LTM4673 PMBus COMMAND DESCRIPTION MFR_EE_DATA Data Contents BIT(S) SYMBOL OPERATION b[7:0] Mfr_ee_data[7:0] To read user space 1) Use the appropriate Mfr_ee_unlock sequence to configure for Mfr_ee_data commands with or without PEC. 2) Read Mfr_ee_data[0] = PackingId (MFR Specific ID). 3) Read Mfr_ee_data[1] = NumberOfUserWords (total number of 16-bit word available). 4) Read Mfr_ee_data[2] through Mfr_ee_data[NumberOfWord+1] (User EEPROM data contents) To write user space 1) Initialize the user memory using the sequence described for the MFR_EE_ERASE command. -
Page 82: Input Current And Energy
LTM4673 PMBus COMMAND DESCRIPTION INPUT CURRENT AND ENERGY DEFAULT COMMAND NAME DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM VALUE PAGE MFR_EIN 0xC0 Input energy data bytes. R Block MFR_EIN_CONFIG 0xC1 Configuration register for energy and input current. R/W Byte 0x00 MFR_IIN_CAL_GAIN_TC 0xC3 Temperature coefficient applied to IIN_CAL_GAIN. R/W Word 0x0000 MFR_IIN_CAL_GAIN... -
Page 83: Mfr_Ein
LTM4673 PMBus COMMAND DESCRIPTION MFR_EIN Read only. This 12 byte data block returns the input energy value and time. Once the block read starts, MFR_EIN updates are suspended until the block read completes. However, energy and time continue to accumulate internally during block reads. -
Page 84: Mfr_Iin_Cal_Gain
LTM4673 PMBus COMMAND DESCRIPTION MFR_IIN_CAL_GAIN The MFR_IIN_CAL_GAIN command is used to set the ratio of the voltage at the input current sense pins to the sensed current. For devices using a fixed current sense resistor, it is the same value as the resistance of the sense resistor (units are expressed in mΩ). -
Page 85: Output Voltage Commands And Limits
LTM4673 PMBus COMMAND DESCRIPTION OUTPUT VOLTAGE COMMANDS AND LIMITS COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM DEFAULT VALUE PAGE VOUT_MODE 0x20 Output voltage data format and mantissa R Byte 0x13 –13 exponent (2 VOUT_COMMAND 0x21 Servo target. Nominal DC/DC converter output Pg00: 1.0 0x2000 voltage setpoint. -
Page 86: Vout_Mode
BIT(S) SYMBOL OPERATION b[7:5] Vout_mode_type Reports linear mode. Hard-wired to 000b. b[4:0] Vout_mode_parameter Linear mode exponent. 5-bit two’s complement integer. Hardwired to 0x13 (–13 decimal). VOUT_COMMAND, VOUT_MAX, VOUT_MARGIN_HIGH, VOUT_MARGIN_LOW, VOUT_OV_FAULT_LIMIT, VOUT_OV_WARN_LIMIT, VOUT_UV_WARN_LIMIT, VOUT_UV_FAULT_LIMIT, POWER_GOOD_ON and POWER_GOOD_OFF These commands provide various servo, margining and supervising limits for a channel’s output voltage. -
Page 87: Output Current Commands And Limits
LTM4673 PMBus COMMAND DESCRIPTION OUTPUT CURRENT COMMANDS AND LIMITS COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM DEFAULT VALUE PAGE IOUT_CAL_GAIN 0x38 The nominal resistance of the current sense mΩ Trimmed; (typical) element in mΩ. Word Pg00: (2.85mΩ) Pg01: (15.5mΩ) Pg02: (15.5mΩ) Pg03: (2.85mΩ) IOUT_OC_FAULT_LIMIT... -
Page 88: Iout_Uc_Fault_Limit
LTM4673 PMBus COMMAND DESCRIPTION IOUT_OC_FAULT_LIMIT, IOUT_OC_WARN_LIMIT and IOUT_UC_FAULT_LIMIT supervisor fault and warning limits. IOUT_OC_FAULT_LIMIT is internally limited to values greater or equal to zero. The register readback value always returns what was last written and does not reflect internal limiting. IOUT_UC_FAULT_LIMIT is internally limited to values less than zero. -
Page 89: Ot_Fault_Limit, Ot_Warn_Limit, Ut_Warn_Limit And
LTM4673 PMBus COMMAND DESCRIPTION OT_FAULT_LIMIT, OT_WARN_LIMIT, UT_WARN_LIMIT and UT_FAULT_LIMIT These commands provide supervising limits for temperature as measured by the external diode. MFR_TEMP_1_GAIN and MFR_TEMP_1_OFFSET The MFR_TEMP_1_GAIN command specifies the inverse of the temperature sensor ideality factor. The MFR_TEMP_1_ OFFSET allows an offset to be applied to the measured temperature. Calculations using these paged commands are: READ_TEMPERATURE_1 = T •... -
Page 90: Mfr_Iout_Cal_Gain_Theta
LTM4673 PMBus COMMAND DESCRIPTION The best way to understand the self-heating effect inside the inductor is to model the system using the circuit analogy of Figure 57. The 1st order differential equation for the above model may be approximated by the following difference equation: –... -
Page 91: Sequencing Timing Limits And Clock Sharing
LTM4673 PMBus COMMAND DESCRIPTION MFR_IOUT_CAL_GAIN_TAU_INV Data Content BIT(S) SYMBOL OPERATION b[15:0] Mfr_iout_cal_gain_tau_inv Values ≤ 0 set MFR_T_SELF_HEAT to zero. Values ≥ 1 set MFR_T_SELF_HEAT to MFR_IOUT_CAL_GAIN_THETA • READ_IOUT • (V – V ISENSEP ISENSEM SEQUENCING TIMING LIMITS AND CLOCK SHARING DEFAULT COMMAND NAME CODE DESCRIPTION... -
Page 92: Mfr_Restart_Delay
LTM4673 PMBus COMMAND DESCRIPTION MFR_RESTART_DELAY This command essentially sets the off time of a CONTROL pin initiated restart. If the CONTROL pin is toggled off for at least 10µs then on, all dependent channels are disabled, held off for a time = Mfr_restart_delay, then sequenced back on. -
Page 93: Mfr_Powergood_Assertion_Delay
LTM4673 PMBus COMMAND DESCRIPTION MFR_PWRGD_EN Data Contents BIT(S) SYMBOL OPERATION b[2] Mfr_pwrgd_en_chan2 Channel 2. 1 = PWRGD status for this channel is ANDed with PWRGD status for any similarly enabled channels to determine when the PWRGD pin gets asserted. 0 = PWRGD status for this channel does not affect the PWRGD pin. b[1] Mfr_pwrgd_en_chan1 Channel 1. -
Page 94: Fault Responses
LTM4673 PMBus COMMAND DESCRIPTION FAULT RESPONSES DEFAULT COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM VALUE PAGE VOUT_OV_FAULT_RESPONSE 0x41 Action to be taken by the device when an R/W Byte 0x80 output overvoltage fault is detected. VOUT_UV_FAULT_RESPONSE 0x45 Action to be taken by the device when an R/W Byte 0x7F output undervoltage fault is detected. -
Page 95: Vout_Ov_Fault_Response And Vout_Uv_Fault
LTM4673 PMBus COMMAND DESCRIPTION VOUT_OV_FAULT_RESPONSE and VOUT_UV_FAULT_RESPONSE Data Contents BIT(S) SYMBOL OPERATION b[7:6] Vout_ov_fault_response_action, Response action: Vout_uv_fault_response_action 00b: The unit continues operation without interruption. 01b: The unit continues operating for the delay time specified by bits[2:0] in increments of t . -
Page 96: Ot_Fault_Response, Ut_Fault_Response, Vin_Ov
LTM4673 PMBus COMMAND DESCRIPTION IOUT_OC_FAULT_RESONSE and IOUT_UC_FAULT_RESPONSE Data Contents BIT(S) SYMBOL OPERATION b[5:3] Iout_oc_fault_response_retry, Response retry behavior: Iout_uc_fault_response_retry 000b: A zero value for the retry setting means that the unit does not attempt to restart. The output remains disabled until the fault is cleared. 001-111b: The PMBus device attempts to restart the number of times specified by the global Mfr_retry_ count[2:0] until it is commanded off (by the control pin or operation command or both), bias power is removed, or another fault condition causes the unit to shut down. -
Page 97: Ton_Max_Fault_Response
LTM4673 PMBus COMMAND DESCRIPTION TON_MAX_FAULT_RESPONSE This command defines the LTM4673 response to a TON_MAX_FAULT. It may be used to protect against a short- circuited output at startup. After startup use VOUT_UV_FAULT_RESPONSE to protect against a short-circuited output. The device also: •... -
Page 98: Shared External Faults
LTM4673 PMBus COMMAND DESCRIPTION SHARED EXTERNAL FAULTS DEFAULT COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM VALUE PAGE MFR_FAULTB0_PROPAGATE 0xD2 Configuration that determines if a channels R/W Byte 0x00 faulted off state is propagated to the FAULT0 pin. MFR_FAULTB1_PROPAGATE 0xD3 Configuration that determines if a channels R/W Byte 0x00... -
Page 99: Mfr_Faultb0_Response And Mfr_Faultb1
LTM4673 PMBus COMMAND DESCRIPTION MFR_FAULTB0_RESPONSE and MFR_FAULTB1_RESPONSE Data Contents BIT(S) SYMBOL OPERATION b[7:4] Reserved Read only, always returns 0000b. b[3] Mfr_faultb0_response_chan3, Channel 3 response. Mfr_faultb1_response_chan3 0: The channel continues operation without interruption 1: The channel shuts down if the corresponding FAULT pin is still asserted after 10µs. When the FAULT pin subsequently de-asserts, the channel turns back on, honoring TON_DELAY and TON_RISE settings. -
Page 100: Status_Byte
LTM4673 PMBus COMMAND DESCRIPTION STATUS_BYTE The STATUS_BYTE command returns the summary of the most critical faults or warnings which have occurred, as shown in the following table. STATUS_BYTE is a subset of STATUS_WORD and duplicates the same information. STATUS_BYTE Data Contents BIT(S) SYMBOL OPERATION b[7]... -
Page 101: Status_Vout
LTM4673 PMBus COMMAND DESCRIPTION STATUS_VOUT The STATUS_VOUT command returns the summary of the output voltage faults or warnings which have occurred, as shown in the following table: STATUS_VOUT Data Contents BIT(S) SYMBOL OPERATION b[7] Status_vout_ov_fault Overvoltage fault. b[6] Status_vout_ov_warn Overvoltage warning. b[5] Status_vout_uv_warn Undervoltage warning... -
Page 102: Status_Temperature
LTM4673 PMBus COMMAND DESCRIPTION STATUS_INPUT Data Contents BIT(S) SYMBOL OPERATION b[1] IIN overcurrent warn Not supported. Always returns 0. b[0] PIN overpower warn Not supported. Always returns 0. STATUS_TEMPERATURE The STATUS_TEMPERATURE command returns the summary of the temperature faults or warnings which have occurred, as shown in the following table. -
Page 103: Status_Mfr_Specific
LTM4673 PMBus COMMAND DESCRIPTION STATUS_MFR_SPECIFIC The STATUS_MFR_SPECIFIC command returns manufacturer specific status flags. Bits marked CHANNEL = All are not paged. Bits marked STICKY = Yes stay set until a CLEAR_FAULTS is issued or the channel is commanded on by the user. -
Page 104: Mfr_Common
LTM4673 PMBus COMMAND DESCRIPTION MFR_PADS Data Contents BIT(S) SYMBOL OPERATION b[7:6] Mfr_pads_asel0[1:0] 11: Logic high detected on ASEL0 input pad. 10: ASEL0 input pad is floating. 01: Reserved. 00: Logic low detected on ASEL0 input pad. b[5] Mfr_pads_control1 1: Logic high detected on CONTROL1 pad. 0: Logic low detected on CONTROL1 pad. -
Page 105: Telemetry
LTM4673 PMBus COMMAND DESCRIPTION TELEMETRY DEFAULT COMMAND NAME CODE DESCRIPTION TYPE PAGED FORMAT UNITS EEPROM VALUE PAGE READ_VIN 0x88 Input supply voltage. R Word READ_IIN 0x89 DC/DC converter input current. R Word READ_PIN 0x97 DC/DC converter input power. R Word READ_VOUT 0x8B DC/DC converter output voltage. -
Page 106: Read_Iout
LTM4673 PMBus COMMAND DESCRIPTION READ_IOUT This command returns the most recent ADC measured value of the channel’s output current. MFR_IIN_PEAK This command returns the maximum ADC measured value of the input current. This register is reset to 0x7C00 (–2 ) when the LTM4673 emerges from power-on reset or when a CLEAR_FAULTS command is executed. MFR_IIN_MIN This command returns the minimum ADC measured value of the input current. -
Page 107: Mfr_Read_Iout
LTM4673 PMBus COMMAND DESCRIPTION MFR_READ_IOUT This command returns the most recent ADC measured value of the channel’s output current, using a custom format that provides better numeric representation granularity than the READ_IOUT command for currents whose absolute value is between 2A and 82A. MFR_READ_IOUT Data Contents BIT(S) SYMBOL OPERATION... -
Page 108: Mfr_Iout_Sense_Voltage
LTM4673 PMBus COMMAND DESCRIPTION MFR_IOUT_SENSE_VOLTAGE This command returns the absolute value of the voltage measured between I and I during the last SENSEPn SENSEMn READ_IOUT ADC conversion without any temperature correction. MFR_IOUT_SENSE_VOLTAGE Data Contents BIT(S) SYMBOL OPERATION b[15:0] Mfr_iout_sense_voltage Absolute value of raw voltage conversion measured between I and I SENSEPn SENSEMn... -
Page 109: Mfr_Temperature_1_Min
LTM4673 PMBus COMMAND DESCRIPTION MFR_TEMPERATURE_1_MIN This command returns the minimum measured value of the power stage temperature sensor in °C. This register is reset to 0x7BFF (approximately 2 ) when the LTM4673 emerges from power-on reset or when a CLEAR_FAULTS command is executed. -
Page 110: Mfr_Fault_Log_Clear
LTM4673 PMBus COMMAND DESCRIPTION MFR_FAULT_LOG_CLEAR This command initializes the EEPROM block reserved for fault logging. Any previous fault log stored in EEPROM will be erased by this operation and logging of the fault log RAM to EEPROM will be enabled. Make sure that Mfr_fault_ log_status_ram = 0 before issuing the MFR_FAULT_LOG_CLEAR command. - Page 111 LTM4673 PMBus COMMAND DESCRIPTION Table 8. Data Block Contents Table 8. Data Block Contents DATA BYTE* DESCRIPTION DATA BYTE* DESCRIPTION Position_last[7:0] Position of fault log pointer Mfr_iout_peak1[7:0] when fault occurred. Mfr_iout_peak1[15:8] SharedTime[7:0] 41-bit share-clock counter value Mfr_iout_min1[7:0] when fault occurred. Counter LSB is in 200μs increments. Mfr_iout_min1[15:8] SharedTime[15:8] Mfr_vout_peak2[7:0]...
- Page 112 LTM4673 PMBus COMMAND DESCRIPTION Table 8. Data Block Contents Table 9. Interpreting Cyclical Loop Data DATA BYTE* DESCRIPTION POSITION DATA Fault_log [Position_last] Read_iin[15:8] Fault_log [Position_last-1] Read_pin[7:0] Read_pin[15:8] Read_vout1[7:0] Fault_log [Position_last-170] Read_vout1[15:8] Reserved 238– Status_vout1[7:0] Number of loops: (238 – 79)/58 Status_mfr_specific1[7:0] = 2.7 Read_temperature_1_1[7:0] *Note that PMBus data byte numbers start at 1 rather than 0.
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Page 113: Mfr_Fault_Log Read Example
LTM4673 PMBus COMMAND DESCRIPTION MFR_FAULT_LOG Read Example PREAMBLE INFORMATION The following table fully decodes a sample fault log read BYTE BYTE NUMBER NUMBER with Position_last = 13 to help clarify the cyclical nature DECIMAL DATA DESCRIPTION of the operation. Mfr_pin_min[15:8] Data Block Contents Mfr_vout_peak1[7:0] PREAMBLE INFORMATION... - Page 114 LTM4673 PMBus COMMAND DESCRIPTION PREAMBLE INFORMATION CYCLICAL MUX LOOP DATA BYTE BYTE LOOP NUMBER NUMBER BYTE BYTE BYTE DECIMAL DATA DESCRIPTION NUMBER NUMBER NUMBER 54 BYTES PER DECIMAL DECIMAL MUX LOOP 0 LOOP Mfr_temperature_ min3[7:0] Status_vout0[7:0] Mfr_temperature_ Read_vout0[15:8] min3[15:8] Read_vout0[7:0] Mfr_iout_peak3[7:0] Read_ Mfr_iout_peak3[15:8]...
- Page 115 LTM4673 PMBus COMMAND DESCRIPTION CYCLICAL MUX LOOP DATA CYCLICAL MUX LOOP DATA LOOP LOOP BYTE BYTE BYTE BYTE BYTE BYTE NUMBER NUMBER NUMBER 54 BYTES PER NUMBER NUMBER NUMBER 54 BYTES PER DECIMAL DECIMAL MUX LOOP 1 LOOP DECIMAL DECIMAL MUX LOOP 1 LOOP Status_vout2[7:0]...
- Page 116 LTM4673 PMBus COMMAND DESCRIPTION CYCLICAL MUX LOOP DATA CYCLICAL MUX LOOP DATA LOOP LOOP BYTE BYTE BYTE BYTE BYTE BYTE NUMBER NUMBER NUMBER 54 BYTES PER NUMBER NUMBER NUMBER 54 BYTES PER DECIMAL DECIMAL MUX LOOP 2 LOOP DECIMAL DECIMAL MUX LOOP 2 LOOP Status_mfr_...
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Page 117: Identification/Information
LTM4673 PMBus COMMAND DESCRIPTION CYCLICAL MUX LOOP DATA CYCLICAL MUX LOOP DATA LOOP LOOP BYTE BYTE BYTE BYTE BYTE BYTE NUMBER NUMBER NUMBER 54 BYTES PER NUMBER NUMBER NUMBER 54 BYTES PER DECIMAL DECIMAL MUX LOOP 3 LOOP DECIMAL DECIMAL MUX LOOP 3 LOOP Read_... -
Page 118: Capability
LTM4673 PMBus COMMAND DESCRIPTION CAPABILITY The CAPABILITY command provides a way for a host system to determine some key capabilities of the LTM4673. CAPABILITY Data Contents BIT(S) SYMBOL OPERATION b[7] Capability_pec Hard coded to 1 indicating Packet Error Checking is supported. Reading the Mfr_config_all_pec_en bit will indicate whether PEC is currently required. -
Page 119: Package Description
LTM4673 PACKAGE DESCRIPTION PIN ID FUNCTION PIN ID FUNCTION PIN ID FUNCTION PIN ID FUNCTION PIN ID FUNCTION OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 OUT0 – TSENSE0 PHMODE0 TSENSE0 INTV CLKOUT0 PWRGD0 SGND SGND SGND SGND... - Page 120 LTM4673 PACKAGE DESCRIPTION PIN ID FUNCTION PIN ID FUNCTION PIN ID FUNCTION PIN ID FUNCTION PIN ID FUNCTION OUT2 OUT2 OUT3 OUT2 OUT2 OUT3 OUT2 OUT2 OUT2 OUT2 CLKOUT3 PHMODE3 TRACK/SS2 RUN3 PWRGD3 RUN2 PWRGD2 COMP3b FREQ3 MODE/CLKIN3 MODE/CLKIN12 COMP3a TRACK/SS3 –...
- Page 121 LTM4673 PACKAGE DESCRIPTION Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications For more information www.analog.com subject to change without notice.
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Page 122: Package Photos
LTM4673 PACKAGE PHOTOS Part marking is either ink mark or laser mark DESIGN RESOURCES SUBJECT DESCRIPTION µModule Design and Manufacturing Resources Design: Manufacturing: • Selector Guides • Quick Start Guide • Demo Boards and Gerber Files • PCB Design, Assembly and Manufacturing Guidelines •...