TPS61042: Can a different voltage from VIN terminal one be connected to power supply side of external inductor?

Hi Kazuya,

We don't have test data under such condition before, please allow me some time to test with EVM and then give you feedback.

BR

Patrick

Hi Patrick,

Thank you very much for your reply.

Unfortunately, we don't have TPS61042 EVM. Your evaluation with EVM would be very helpful for the customer and me.
Could you please test TPS61042 on EVM in the conditions?

Thank you again and best regards,
Kazuya.

Hi Patrick,

I forgot to ask you the following question.
Do you know that any TI LED driver which Inductor power line can be separated from VIN of the device?

If you know it, could you please let me know?

Thank you very much and best regards,
Kazuya.

Hi Kazuya,

I'll test with EVM and give you feedback on maybe next Monday or Tuesday.

Usually boost LED drivers with peak current mode can separate Vin and inductor.

But for those using constant on-time control devices, better to have a bench test.

May I ask why you need a separate power supply?

BR

Patrick

Hi Patrick,

Thank you very much for your strong supports. I'm looking forward to receiving the evaluation result.
The customer is considering using TPS61042 for their portable equipment which works with 2 cell lithium-ion battery(5.4V~8.4V).
3.3V power line for CPU is generated from this battery by a buck converter. TPS61042 device power is connected to this 3.3V.
But they want to connect the power supply side of inductor of tps61042 to the battery directly for efficiency improving and noise reducing on 3.3V power line.

Thank you again and best regards,
Kazuya.  
  

Hi Kazuya,

Based on bench test, I didn't see any difference with VIN connected with inductor or they are separated.

But I only tested with one board, so I think it's still better to follow datasheet guide.

BR

Patrick