Trace Oxygen Analyzer Operational Theory
Teledyne Analytical Instruments 7
2.3.2 Signal Processing
Figure 2-1 is a block diagram of the signal processing electronics
described below.
Figure 2-1: Block Diagram of the Signal Processing Electronics
In the presence of oxygen, the sensor(s) produce a current. A
current to voltage amplifier (I–E AMPL) converts this current to a
voltage.
The output from the I-E amplifier and subsequent buffer circuit (not
shown) is sent to an analog to digital converter (ADC), and the resulting
digital concentration signal is sent to the micro controller.
The digital concentration signal along with input from the front
panel buttons (KEYBOARD) is processed by the micro controller, and
appropriate output signals are directed to the display, alarm relays, and