Tool/software:
Hello everyone,
I'm working with the UC2842 and I'm trying to lower its operating frequency when the input voltage is high.
My approach is to use a hysteresis circuit that turns on a transistor when the input voltage exceeds 700V. This transistor adds a parallel capacitor between the RT/CT pin and ground. My expectation was that increasing the total CT would lower the oscillator frequency.
However, in my testing, the operating frequency has unexpectedly increased by about 5 times instead of decreasing.
Could anyone provide some insight into why this might be happening? Also, are there any alternative methods you would recommend for reducing the UC2842's frequency at higher input voltages?
Any advice would be greatly appreciated.
Thanks,
