K8055 PWM giving voltage, not open collector

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1

Hi all,

I’m having an issue with my k8055 board. The pwm1 terminal is giving a 5v signal, while the pwm2 terminal is giving the correct open collector signal. Any idea what might be causing this?

Cheers.

2

It seems the base driving voltage of transistor T1 is output from the PWM1 terminal.
Possible cause:

  • Emitter terminal of transistor T1 is not properly soldered to GND.
  • Transistor T1 is defective.