Service manual

4. BOARD/UNIT DESCRIPTION
4.8 Service Manual BSM-4100
The motherboard isolates the analog boards such as ECG RESP1 to 3 boards, SpO
2
board and MP1 to 3 boards from the ground. The motherboard supplies the
isolated power to each analog board. The motherboard transfers the vital sign
signals from the analog boards to the DPU board. The motherboard transfers the
control signals from the DPU board to the analog boards.
The motherboard lets the two ECG RESP1 to 3 boards communicate. The ECG and
respiration waveforms (analog signals) for arrhythmia detection and screen display
are multiplexed on the motherboard and sent to the DPU board. 12 lead ECG
signals digitized on the ECG RESP3 board are transferred to the DPU board.
The status signal of NIBP cuff size for adult/child or neonate is transferred to the
DPU board together with ECG floating status communication.
The voltages (analog signals) measured for SpO
2
are multiplexed at 2 ms interval
on the SpO
2
board. The multiplexed analog signals are sent to the DPU board
through the motherboard.
The vital sign input signals on the MP1 to 3 boards are digitized by the A to D
converter controlled by the CPU on the MP2 board. The digital data is transferred
to the DPU board through the motherboard.
Motherboard
ECG RESP2
or
NELLCOR SpO2
NK SpO2
MP2
Patient Circuit Isolation
to DPU board
Communication
Power supply
Vbus, +5 V and 3.3 V
ECG/BP out
from DPU board
(Isolated on DPU board)
ECG RESP3
with CUFF status
MP3