GE Dash 3000 Service Manual page 54

Debug patient monitor and diagnostic LEDs
Main DC-DC converter section
Battery subsystem
2-34
Equipment overview: Theory of operation
An integrated debugger operating in the debug mode within the main
processor provides basic emulator-like features such as modification of
register and memory locations and setting of breakpoints. The connector
required for this serial communication is a dual row 10-pin header. This
connector is located within the patient monitor and is not intended for
field service use. Tracing of instructions and logic analysis is provided by
an adapter board that connects to a socket installed on the main
processor board instead of the microprocessor.
Three diagnostic LEDs located along the front edge of the board are
provided for general purpose use and are under software control. The
LEDs interface directly to port A of the microprocessor. A flashing green
LED indicates normal monitoring operation.
The main DC-DC converter consists of two independent synchronous
rectifier buck regulators with one common controller.
The patient monitor uses a "point of use" power conversion architecture
with +9-18 V being the main power distribution bus.
Four voltage outputs are developed on the processor/power management
PCB:
+3.3 V,

+5 V,

+12 V, and

–12 V.

Each one of the four outputs are individually current limit protected
against overload and short circuit.
Battery charging and control is accomplished on the processor/power
management PCB.
The battery is a smart battery and features an on-pack fuel gauge.
Dash 3000/4000/5000 2000966-542D