UC2525A: Setting frequency of Oscillator

SIDDHESH KALA

Part Number: UC2525A

Tool/software:

Hi,

I wanted to set the oscillator frequency roughly 100kHz, So I used Rt = 13.3kohm and Ct = 1nF. But when I measured the output using an oscilloscope, I got the frequency output as 88kHz.

Please can you just what can be done.

1 month ago

0 Hong Huang 1 month ago

TI__Guru 73265 points

Hi,

Can you show how you did calculation to get 100kHz?

The Fig 1 shows oscillator frequency about 160kHz, so switching frequency fsw = 80kHz if you configure the IC to two switch topology.

0 SIDDHESH KALA 1 month ago

Prodigy 40 points

I used the below formula which is mentioned in the datasheet

0 Hong Huang 1 month ago in reply to SIDDHESH KALA

TI__Guru 73265 points

Hi,

That equation is not accurate so only provides numbers nearby. RD is also affecting the result.

In reality, you need to tune up RT to get the frequency you want to have.

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UC2525A: Setting frequency of Oscillator