DRV103: Duty cycle of PWM Signal not accurate as per datasheet declared resistor value

kirubakar Nagarajan

Part Number: DRV103

Hi Team,

Good Day...

This is Kirubakar Nagarajan from Rotork Controls Limited. I have implemented DRV103H IC for solenoid driving with 50% duty cycle. I have used 215K resistor for setting IC oscillator frequency @ 24KHz and 137K Resistor implemented to have 50% duty cycle of PWM signal output from DRV IC. All resistor tolerance are selected with 1% limit and when I captured the signal in DSO, the duty cycle is not 50%. Could you please clarify the issue.

I have attached the waveform for your reference.

over 1 year ago

0 David Medis over 1 year ago

TI__Mastermind 19300 points

Hi Kirubakar,

I will look into this issue and get back to you within 24 hours.

Best,

David

0 David Medis over 1 year ago

TI__Mastermind 19300 points

Hi Kirubakar,

To achieve a PWM signal with a more accurate duty cycle of 50%, I would suggest decreasing your RFREQ resistor from 215 kΩ to 205 kΩ. This should change your frequency from 24 kHz to 25 kHz.

In order to achieve 50% duty cycle the RPWM should be 137 kΩ at 25 kHz.

Best,

David

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DRV103: Duty cycle of PWM Signal not accurate as per datasheet declared resistor value