BCI Capnocheck Plus - Oximeter Board Signal Dictionary

analog switch U7. The output of the integrator is passed through offset stage
Chapter 4: Oximeter Board Circuit Description
U10A and then routed to the ADC for measurement.
Signal Dictionary
This section lists, in alphabetical order, the signal names used on the
schematics.
Oximeter Board
. The signal’s origin, destination, and purpose are described.
SIGNAL DESCRIPTION
/AMB-FAULT Signal informing microcontroller about excess of ambient light.
AMB
Signal adding offset to the integrator U8A.
ANAS The +5 volt power supply VCC is filtered to produce ANA+5. ANA+5 powers the
analog circuitry.
“o ANA-5 The -5 volt power supply is filtered to produce ANA-5. ANA-5 powers the analog
circuitry.
CAP-GND Signal used to short blocking capacitor C22 to ground.
CKS CKS is the high-speed, synchronous serial output clock signal.
CON2,
CON3
Probe LED's driving signals
INTGRAT,
RST-INT
Signals used to control integrator UBA.
IR-DRV,
RED-DRV,
AR-ENBL,
/RED-ENBL
Signals used to control MOSFET H-bridge Q4 and Q5, which powers probe LED's.
LED-DRV
Signal which defines LED drive current.
POT-LD POT-LD is used to select digital potentiometer chip U11.
PRB-DET PRB-DET is used to inform microcontroller if probe is plugged in.
/PRB-FAULT Signal used to inform microcontroller about probe cable problem.
SIGNAL SIGNAL originates at TP6 and is routed to ADC U6 input.
TXS -| TXS is the high-speed, synchronous serial output transmitted data signal.
TXA1, RXA1 Asynchronous serial communication signals on the Master side.
V-AMB V-AMB is the output of the front-end differential amplifier.
V-R
2.500 VDC reference voltage.
VREF 3.4 VDC reference voltage.
VCC
VCC
is the regulated +5 VDC supply generated by +5 volt power supply regulator
chip U3 and its discrete components.
vss Digital ground.
Capnocheck Plus Service. Manual
4-3