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ELECTRICAL CHARACTERISTICS
Note 4: The two power inputs—V
outputs—V
and V
—are tested independently in production. A
OUT0
OUT1
shorthand notation is used in this document that allows these parameters
to be referred to by "V
" and "V
INn
a value of 0 or 1. This italicized, subscripted "n " notation and convention
is extended to encompass all such pin names, as well as register names
with channel-specific, i.e., paged data. For example, VOUT_COMMANDn
refers to the VOUT_COMMAND command code data located in Pages 0
and 1, which in turn relate to channel 0 (V
Registers containing non-page-specific data, i.e., whose data is "global" to
the module or applies to both of the module's channels lack the italicized,
subscripted "n ", e.g., FREQUENCY_SWITCH.
Note 5: V
(DC) and line and load regulation tests are performed in
OUTn
production with digital servo disengaged (MFR_PWM_MODEn[6] = 0b)
and low V
range selected MFR_PWM_MODEn[1] = 1b. The digital
OUTn
servo control loop is exercised in production (setting MFR_PWM_
MODEn[6] = 1b), but convergence of the output voltage to its final settling
value is not necessarily observed in final test—due to potentially long
time constants involved—and is instead guaranteed by the output voltage
readback accuracy specification. Evaluation in application demonstrates
capability; see the Typical Performance Characteristics section.
Note 6: See output current derating curves for different V
located in the Applications Information section.
Note 7: Even though V
and V
OUT0
maximum, the maximum recommended command voltage to regulate
output channels 0 and 1 is: 1.8V with V
the MFR_PWM_MODEn[1] = 1b.
Note 8: Minimum on-time is tested at wafer sort.
Note 9: The data conversion is done by default in round robin fashion. All
inputs signals are continuously converted for a typical latency of 90ms.
Setting MFR_ADC_CONTRL value to be 0 to 12, LTM4700 can do fast
data conversion with only 8ms to 10ms. See section PMBus Command
for details.
Note 10: The following telemetry parameters are formatted in PMBus-
defined "Linear Data Format", in which each register contains a word
comprised of 5 most significant bits—representing a signed exponent, to
be raised to the power of 2—and 11 least significant bits—representing
a signed mantissa: input voltage (on SV
command code; output currents (I
command codes; module input current (I
the READ_IIN command code; channel input currents (I
accessed via the MFR_READ_IINn command codes;and duty cycles of
channel 0 and channel 1 switching power stages, accessed via the
READ_DUTY_CYCLE
command codes. This data format limits the
n
resolution of telemetry readback data to 10 bits even though the internal
ADC is 16 bits and the LTM4700's internal calculations use 32-bit words.
Note 11: The absolute maximum rating for the SV
voltage telemetry (READ_VIN) is obtained by digitizing a voltage scaled
down from the SV
pin.
IN
Note 12: These typical parameters are based on bench measurements and
are not production tested.
and V
—and their respective power
IN0
IN1
", where n is permitted to take on
OUTn
) and channel 1 (V
OUT0
OUT1
, V
, and T
IN
OUT
are specified for 6V absolute
OUT1
range-setting bit set low using
OUT
), accessed via the READ_VIN
IN
), accessed via the READ_IOUTn
OUTn
+ I
+ I
), accessed via
VIN0
VIN1
SVIN
+ 1/2 • I
VINn
pin is 18V. Input
IN
For more information
Note 13: EEPROM endurance and retention are guaranteed by wafer-level
testing for data retention. The minimum retention specification applies
for devices whose EEPROM has been cycled less than the minimum
endurance specification, and whose EEPROM data was written to at 0°C
≤ T
≤ 85°C. The RESTORE_USER_ALL or MFR_RESET is valid over
J
the entire operating temperature range and does not influence EEPROM
characteristics.
Note 14: Channel 0 OV/UV comparator threshold accuracy for
).
MFR_PWM_MODEn[1] = 1b tested in ATE at V
0.5V and 1.8V. 1V condition tested at IC-Level, only. Channel 1 OV/UV
comparator threshold accuracy for MFR_PWM_MODEn[1] = 1b tested
+
in ATE with V
– V
VOSNS
IC-level, only. MFR_PWM_MODEn[1] = 1b is the Low Range.
Note 15: Tested at IC-level ATE.
Note 16: The LTM4700 quiescent current (I
the I
of EXTV
.
Q
CC
Note 17: The LTM4700's EEPROM temperature range for valid write
commands is 0°C to 85°C. To achieve guaranteed EEPROM data retention,
execution of the "STORE_USER_ALL" command—i.e., uploading RAM
contents to NVM—outside this temperature range is not recommended.
However, as long as the LTM4700's EEPROM temperature is less than
,
A
130°C, the LTM4700 will obey the STORE_USER_ALL command. Only
when EEPROM temperature exceeds 130°C, the LTM4700 will not act
on any STORE_USER_ALL transactions: instead, the LTM4700 NACKs
the serial command and asserts its relevant CML (communications,
memory, logic) fault bits. EEPROM temperature can be queried prior
to commanding STORE_USER_ALL; see the Applications Information
section.
Note 18: The LTM4700 includes overtemperature protection that is
intended to protect the device during momentary overload conditions.
Junction temperature will exceed 125°C when overtemperature protection
is active. Continuous operation above the specified maximum operating
junction temperature may impair device reliability.
Note 19: See 50A distribution on Page 14. Tested at 25A load due to
manufacturing tester equipment limitation.
62
56
50
43
),
SVIN
37
31
25
19
12
6
0
0
Figure 1. Programmable R
www.analog.com
LTM4700
+
– V
VOSNS0
–
= 0.5V and 1.8V. 1.5V condition tested at
VOSNS
) equals the I
Q
5
10
15
20
25
30
CODE
4700 F01
COMP
–
=
VOSNS0
of V
plus
Q
IN
35
Rev. B
11
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