Control Automatic Quality Control (Aqc) Valve Stepper Circuitry; Power System Protection And Input Circuitry - Bayer HealthCare RapidPoint 400 Series Service Manual

Control Automatic Quality Control (AQC) Valve Stepper Circuitry

This section Main board contains IC U32, which takes digital latched
signals from RTP CPLD U38 and forms the proper sequencing signals to
drive the automatic quality control (AQC) position motor that will be located
in the AQC module. The driver signals exit the Main board through
connector J4. This connector also provides +5 V power and dualopto
signals for the AQC module.

Power System Protection and Input Circuitry

This section Main board contains the 24-pin connector, J25. This
connector delivers all power supply voltages from the system power
supply.
Power Supply
Voltage
+12_VDC supply
-12_VDC supply
+5_VDC supply
VCC supply
AUX5V supply
DIS5V supply
DISVCC supply
BKLTVCC supply
J24 floppy power
connector
Transient protector U59 protects the +24 V supply from overvoltage. The
+24 V supply is current limited from shorts by fuse F2. This supply drives
motors through diode U53, which clamps the motor current monitoring
circuit to 0.2 V. This supply also splits to drive heaters through power
transistor.
90
Description
Overvoltage protected by transient protector U42 and is
current limited from shorts by R174.
Overvoltage protected by transient protector U51 and is
current limited from shorts by R173.
Overvoltage protected by transient protector U52 and is
current limited from shorts by R243, R218, R244.
Overvoltage protected by transient protector U52 and is
current limited from shorts by R243, R218, R244.
Overvoltage protected by transient protector U52 and is
current limited from shorts by R245.
Drives the thermal printer print head and is current limited
from shorts by R196, R195, and R230.
Drives the logic ICs in the display module and is current
limited from shorts by R2.
Drives the backlight inverter in the display module and is
current limited from shorts by R41.
Drives the diskette drive on the main assembly and is current
limited from shorts by R1.
Rev. C