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UX-B800A

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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

NO.

PIN NAME

PIN DESCRPTION

DC1_A or DC1+

Pos output for DC mtr drvr #1

GND

Ground

DC1B or DC1-

Neg output for DC Mtr drvr #1