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Inputs:
NODE (+) A2J7-26(PWM-ON) A2J7-25(PWM-OFF)
NODE (+)
Outputs:
NODE | MEASUREMENT | SOURCE |
M | 1.7∝s, 20KHz pulse(see Waveform #1) | |
M | 10∝s, 20KHz pulse(see Waveform #2) | |
NODE | MEASUREMENT | SOURCE |
10.6Vdc | ||
39Vdc | A1C51 ( + | |
|
| A1Cl( - |
NODE (+) | NODE | MEASUREMENT |
(see Waveform #3) | ||
(see Waveform #3) | ||
(see Waveform #4) | ||
(see Waveform #5) |
If you replace the FETs, replace both the FETs and associated drive components as furnished in FET Service Kit. Agilent Part No.
The FETs are static sensitive and can be destroyed by relatively low levels of electrostatic voltage. Handle the A4 FET board and the FETs only after you, your work surface and your equipment are properly grounded with appropriate resistive grounding straps. Avoid touching the FET's gate and source pins.
Troubleshooting Bias Supplies
+5V On A2 Control Board. The PWM A2U22 includes a clock generator (40KHz set by A2R170, A2C79 and A2Q10), and a current limit (2Adc set by 0.15Vdc across A2R172). It turns off each output pulse using the difference between the voltage at voltage divider
Circuit Included. +5Vdc bias supply circuitry from connector pins
Setup. The Main Troubleshooting Setup, Page 53. Apply the ac mains voltage to the voltage transformer, and set the external supply to 0Vdc.
Input: |
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NODE (+) | NODE | MEASUREMENT | SOURCE | |
≈ 21Vdc |
| A1CR2,A1CR5 | ||
Outputs: |
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NODE ( + ) |
| NODE | MEASUREMENT | |
| ≈2 to 4Vdc sawtooth, 40KHz | |||
| " | ≈ 19V pk, 15∝s pulses, 40KHz | ||
A2Q9 (emit) |
| " | ≈ 20V pk, 5∝s pulses, 40KHz | |
| " | 2.5 Vdc |
| |
A2R161, A2R163 |
| " | 2.5 Vdc |
|
To check if load on + 5V is shorted, remove jumper A2W3
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