Teledyne Camera Accessories T100 Manual Do Utilizador

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Principles of Operation 
Teledyne API - T100 UV Fluorescence SO2 Analyzer  
306 
 
CO
OLE
R
 (Closed Loop
To  
Motherboard
 
   PMT Preamp PCA 
E Test Control 
From CPU
 
D-A 
Converter 
PMT 
Coarse 
Gain Set 
(Rotary 
PMT Fine 
Gain Set 
(Rotary 
Switch) 
PMT 
Signal 
Offset
 
E-Test 
Generator
 
O-Test 
Generator
 
O Test Control 
From CPU
 
PMT Temp 
Sensor
 
PMT 
Temperature 
Feedback 
Circuit
 
TEC Control 
PCA
 
PMT Output
 
PMT HVPS 
Drive Voltage
 
PMT Temp Analog Signal 
to Motherboard
 
PMT Output Signal 
(PMT) to Motherboard
 
O Test 
LED
 
Amp to 
Voltage 
Converter/
Amplifier 
Low Pass 
Noise 
Filter 
 
MUX 
 
 
Figure 13-20:  PMT Preamp Block Diagram 
The PMT temperature control loop maintains the PMT temperature around 7° C and can 
be viewed as test function PMT TEMP on the front panel (refer to Section 4.1.1). 
The electrical test (ETEST) circuit generates a constant, electronic signal intended to 
simulate the output of the PMT (after conversion from current to voltage). By bypassing 
the detector’s actual signal, it is possible to test most of the signal handling and 
06807C DCN6650