LM76003: PWM Input and Programmable Output.

Ramya L

Part Number: LM76003

Hi Good afternoon,

For the above mentioned part number LM76003, to obtain the dynamically programmable output voltage, from 6 to 24 volts, according the duty cycle of PWM signal, which is taken as input.

1. How can I make a setup at the input side, so as to receive a PWM signal of frequency 50 Hz , having a time period 1 us, and duty cycle from 5% to 10%.

2. How can I get a output voltage programmable according to the duty cycle of PWM signal received.

Please guide and do the helpful.

Thanking you in advance

Ramya.L

over 4 years ago

0 Andy Chen over 4 years ago

TI__Mastermind 27045 points

Hi Ramya,

Normally the PWM signal is filtered by Low Pass Filter to get the average DC level which is proportional to the duty cycle, the output voltage can be programmed by the DC level biased on FB pin.

Do you have any limitation on the freq of PWM signal? 50Hz is too low for the low pass filter design. normally PWM freq range 1KHz~100KHz is better choice.

B R
Andy

0 Ramya L over 4 years ago in reply to Andy Chen

Prodigy 80 points

Thanks for the reply Andy,

Yes we can convert 50Hz signal to 1KHz . But can you please let me know through which pin should I take in the PWM signal?

And using RC filter , can we achieve it?

0 Andy Chen over 4 years ago in reply to Ramya L

TI__Mastermind 27045 points

Hi Ramya,

Have you finished your circuit design, pls upload it so I can show you how to bias it.

B R
Andy

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LM76003: PWM Input and Programmable Output.