TPS92692-Q1: TPS92692-Q1

Daniel Campano

Part Number: TPS92692-Q1
Other Parts Discussed in Thread: TPS92692, TPS92691

Hi All,

I have read that when PWM dimming is not required the : "When dimming is not required, connect the DIM/PWM pin to the VCC pin". Does it mean it will also disable analog dimming if I connected DIM/PWM pin to Vcc?

If I don't need to use PWM dimming do I still have to use the P-FET dimming connected to PDRV?

Regards

over 3 years ago

0 Tuan Tran74 over 3 years ago

TI__Genius 17690 points

Hi Daniel,

Pulling up DIM/PWM to VCC will just put PWM dimming at 100% ON and not effect analog dimming. They are two separate things. If you don't need PWM dimming then you might not need to have the P-FET depending on your FAULT and protection requirements. For a the Boost topology you cannot protect against output over current if the input voltage is higher than the output LED voltage or output short since we use that P-FET to disconnect the load.

Thanks Tuan

0 Daniel Campano over 3 years ago in reply to Tuan Tran74

Intellectual 470 points

Is there any design reference without the P-FET and without PWM, just using dim analog dimming for boost topology?

0 Tuan Tran74 over 3 years ago in reply to Daniel Campano

TI__Genius 17690 points

Hi Daniel,

All of our reference design uses the P-FET. Again, the P-FET is only used for PWM dimming and FAULT protection. You can get an eval board for the TPS92692 to help with your design.

https://www.ti.com/tool/TPS92692EVM-880?keyMatch=TPS92692&tisearch=Search-EN-everything&usecase=GPN

Thanks Tuan

0 Daniel Campano over 3 years ago in reply to Tuan Tran74

Intellectual 470 points

Hi Tuan,

Just to be sure. Can I then connect the DIM/PWM to VCC and remove the P-FET ( so I wouldn't use the pin PDRV) and I can still dim the LED current using analog dimming?

If I don't use the P-FET can I leave PDRV floating or it needs to be connected to GND?

Thanks in advance.

0 Tuan Tran74 over 3 years ago in reply to Daniel Campano

TI__Genius 17690 points

Hi Daniel,

Yes, you can connect DIM/PWM to VCC and remove the P-FET while still using analog diming with the IADJ pin. You can leave the PDRV pin floating...Do not connect this pin to ground.

Thanks Tuan

0 Daniel Campano over 3 years ago in reply to Tuan Tran74

Intellectual 470 points

Hi Tuan,

Thanks for your answer. Finally I am going to do the design for TPS 92691. I think I can still connect DIM/PWM to VCC while I still use analog dimming with IADJ pin for TPS92691, is this correct?. I guess DDRV I can also leave open right?

0 Tuan Tran74 over 3 years ago in reply to Daniel Campano

TI__Genius 17690 points

Daniel,

Yes, you can do the same with the TPS92691.

Thanks Tuan

Power management

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TPS92692-Q1: TPS92692-Q1