Sharp UX-B800A Service Manual page 81

2.5. IC600 (14D0830) Hardware description
This specfication describes a multifunction analog ASIC to be used in
inkjet printer applications. This ASIC integrates two Switching Voltage
Regulator circuits, two motor drive circuits and a Reset circuit in a sin-
gle IC.
2.5.1 Switching voltage regulators
The ASIC is to support two, buck type, switching, voltage regulators.
Each is of the comparitor type, without linear error amplifiers or exter-
nal compensation networks. For each regulator, the ASIC is to contain:
a comparitor with internal reference, internal oscillator, output pass
switch, internal current sense and current limit. An external flyback
diode, inductor, and filter capacitor is to be used. Output voltage is to
be set with an external voltage divider network. VPH_Reg is to be dis-
abled through serial command. VPH_Reg may also be disabled by
means of an inhibit pin. Vcc_Reg is to function at all times. Each regu-
lator has a 1ma minimum load.
The regulators are to be designed to support the voltages and currents
listed below using the internal pass switch and sense resistor.
VPH_Reg will also have the capability to support higher currents than
the internal switch supports, through the addition of an external
MTD3055V MOSFET and current sense resistor. A pin will be brought
out from the gate drive of the internal switch to drive the gate of the
external MOSFET. The external sense resistor will be wired as sug-
gested by the ASIC vender.
Intended voltages and loads:
VPH_Reg: 3A DC Load (Peak/Ave)
+/- 2% Reg reference tolerance
Can be disabled through serial command or inhibit pin.
Output voltage can be set from VREF to 13V using the external resis-
tor divider network.
Vcc_Reg: 1000ma DC Load (Not used)
(+/- 2%) Reg.
Output voltage is intended to supply machine Vcc at 5 or 3.3V. Voltage
is set with an external voltage divider.
2.5.2 Load detect
For VPH_REG, the DC current from the regulator shall be indicated
through an output pin.
2.5.3 2ea. DC motor drivers
Bi-directional, pulse width modulated each with an external PWM
input. These motor drives must be able to support a minimum output of
1.6A for 100ms. For thermal budgeting, the maximum average current
will be 450mA 'long term average' with an average of 750mA over peri-
ods of up to 1 sec. At the current limit (1.6A or greater), the motor drive
should 'chop' at the limited current level. The DC motor direction is
serially controlled.
2.5.4 1ea. Configurable motor driver
This motor drive is selectable to be operated in one of two modes, DC
or stepper. In DC motor mode, the drive is to operate in the same man-
ner as the DC motor drivers previously described. In stepper mode,
the drive is to drive a bipolar stepper motor with average current levels
of 183, 367, and 550 mA per phase with quarter step mode capability.
Phase and current information will be sent over the serial port.
This machine uses "Stepper mode" for TX motor driving. And uses
"DC motor mode" for Carrier motor & Feed motor driving.
IC600 (14D0830) Pin descriptions (1/2)
PIN PIN NAME
NO.
1 DC1_A or DC1+
2 GND
3 DC1B or DC1-
4 DC2B or DC2-
5 GND
6 DC2_A or DC2+
7 VBULK
8 MD2_PWM
9 GND
10 NVPH_Inhibit
11 nRESET
12 SDATA
13 SCLK
14 nCS
15 OASUPPLY
16 OA1OUT
17 OA1+ or oa1plus
18 OA1- or oa1minus
19 OA2OUT
20 OA2+ or oa2plus
21 OA2- or oa2minus
22 OA3OUT
23 OA3+ or oa3plus
24 OA3- or oa3minus
25 OAGND
26 VBULK
27 MD3_OUT_A_A or
cm1A or
MD3_OUT_A+
28 MD3_R_SENSE_A
or rsense1
29 MD3_OUT_A_B or
cm1B or
MD3_OUT_A-
30 MD3_OUT_B_B or
cm2B or
MD3_OUT_B-
31 MD3_R_SENSE_B
or rsense2
32 MD3_OUT_B_A or
cm2A or
MD3_OUT_B+
33 VBULK
34 MD3_MODE or
mode
35 MD3_PWM
36 SWITCH_OUT
37 SWITCH_IN
38 BASE_DR_FB or
v1p8fb
39 BASE_DR_OUT or
v1p8base
40 CPL
41 CPH
42 VP
43 GND
44 VCC_FB
5 – 11
UX-B800A
PIN DESCRPTION
Pos output for DC mtr drvr #1
Ground
Neg output for DC Mtr drvr #1
Neg output for DC Mtr drvr #2
Ground
Pos output for DC mtr drvr #2
20 to 33V Input
Pwm pin for DC mtr drvr #2
Ground
Inhibit pin for VPH reg, active low
nRESET input/output pin
Serial data input
Serial data input clock
Serial input register chip select
Opamp supply voltage
Output for OpAmp #1
Noninverting input for opamp #1
Inverting input for opamp #1
Output for OpAmp #2
Noninverting input for opamp #2
Inverting input for opamp #2
Output for OpAmp #3
Noninverting input for opamp #3
Inverting input for opamp #3
Opamp ground
-
Phase A+ output for motor driver #3
Phase A sense pin. Ground solidly to
ASIC ground, if MD3 used in DC mtr
config.
Phase A- output for motor driver #3
Phase B- output for motor driver #3
Phase B sense pin. Ground solidly to
ASIC ground, if MD3 used in DC mtr
config.
Phase B+ output for motor driver #3
-
Mode pin input for mtr drvr #3
Pwm pin for DC mtr drvr #3
Source pin for printhead Vcc switch
Drain pint for printhead Vcc switch.
Also serves as the power supply for
the Vcc Base Drive circuit.
feedback pin for NPN base drive. Tie
high if not used.
Output drive pin for NPN base drive
Charge pump pin
Charge pump pin
Charge pump storage cap pin
-
Feedback pin for Vcc Reg. Tie high if
not used.