UC1524A: I

David Labore

Part Number: UC1524A

I have been trying to determine the output frequency from using the formula that is in the datasheet and it does not work out to what I have bread boarded. Is there a different formula to determine the output frequency. Could it have anything to do with the voltage. I'm using 15VDC as input voltage. I have 102nF cap and 100K resistor. What should my output Freq be?

over 6 years ago

0 Daniel Hartung over 6 years ago

TI__Mastermind 28345 points

Hey David,

The reason the equation isn't matching up exactly with the equation is because the values you are using are on the edge of values that would normally be used.

Unfortunately its hard to have a linear equation for the frequency response because the way that the device figures out the switching frequency isn't perfectly linear.

Using the equation for your values you should be in the ~112 Hz region. What is the value you are seeing?

Thanks,
Daniel

0 David Labore over 6 years ago in reply to Daniel Hartung

Prodigy 20 points

I'm seeing from 153 Hz to 169 Hz. Trying to get ~166 Hz. I can not get it to be consistent from chip to chip.

0 Daniel Hartung over 6 years ago in reply to David Labore

TI__Mastermind 28345 points

Hey David,

You may want to try a smaller resistor and larger capacitor.

This should make less variation in the switching frequency.

Thanks,
Daniel

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UC1524A: I