CH Tech Pulse Generator User Manual
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4.6
OUTPUT VOLTAGE LEVEL PROGRAMMING
Two 12 bit digital to analog converters (DAC's) provide the output switch reference voltages.
The DAC's have built in safety features to prevent damage if the positive reference is programmed
below the negative voltage; however, the user should try to prevent this situation. The output
logic switches the high and low reference voltages into a power op-amp output stage. The pulse
string from the pulse generation logic provides the control to the switch, while the reference
voltages provide the voltage levels. The op-amp power stage has 2-3 ohms output impedance. A
jumper selectable resistor between the op-amp output and the BNC provides isolation and back
termination. The resulting output impedance is about 5 ohms with jumper J5 installed and 50
ohms with Jumper J6 installed. A load of 50 ohms or more is recommended.