LM74502: The ability to drive EN pin with PWM

Weiwei Su

Part Number: LM74502

Tool/software:

Hi Team,

I'm planning on build a high-side switch with LM74502. But can I drive EN with PWM(250-300Hz)? as I want the switch to have PWM output capability.

6 months ago

0 Shiven Dhir 6 months ago

TI__Mastermind 46370 points

Hi Weiwei,

Yes, it is achievable.

Regards,

Shiven Dhir

0 Weiwei Su 6 months ago in reply to Shiven Dhir

Prodigy 230 points

Shiven,

Just read that on section 9.4 it uses OV pin as logic input, whereas I feel the inverted PWM is not desireable since I will need a spare GPIO to control the EN pin as master switch to temporary turn off the device before the inverted PWM is available otherwise if I just tie EN to VS it would turn on itself whenever the power is on and the inverted PWM signal is not pulled up. If EN pin can be PWMed as well, should I just tie OV into GND? With resistor or without?

0 Shiven Dhir 6 months ago in reply to Weiwei Su

TI__Mastermind 46370 points

Hi Weiwei,

Yes, you can tie OV directly to ground.

Regards,

Shiven Dhir

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LM74502: The ability to drive EN pin with PWM