Detection Of The Input Signal; Analogue Board Control; Analogue Board - Mindray BA-88A Service Manual

4.5.9 Detection of the Input Signal

Figure 4-10 Graph of input signal detection
The system should detect the signal from filter position sensor, aspirate button,
cuvette temp. controlling fan blocking. Before detected by control module, all input
signals should go through the level translation circuit.

4.5.10 Analogue Board Control

Figure 4-11 Graph of analogue board controlling
Three signals are controlled by analogue board: digital potentiometer control signal
(DCPx), channel selection signal (CH), AD collection and control signal (AD_Ox and
AD_lx). All control signals are generated by control module. The signals between the
control module end and analogue board should go through level translation (TTL to
LVTTL).
4.6

Analogue Board

The analogue board realizes the functions of photoelectric signal, temperature
sensor signal modulation and amplification, AD collection.
The photodiode transforms the light signal which has passed through the flow
cell (or cuvette) into voltage signal. The voltage signal will be filtered,
amplified inversely, and finally output at the outputting end of the AD
converter through selectable switch.
4 Hardware 4-7