BQ25750: auto reverse mode will still function within 50us, from charge mode to discharge mode?

Marco Liu

Prodigy 40 points

Part Number: BQ25750

Tool/software:

auto reverse mode will still function within 50us, from charge mode to discharge mode?

3 months ago

0 Ethan Galloway 3 months ago

TI__Mastermind 31035 points

Hello Marco,

Yes, that is correct. Auto reverse mode will trigger in ≈50µs once VAC falls below the ACUV voltage.

Best Regards,
Ethan Galloway

0 Marco Liu 3 months ago in reply to Ethan Galloway

Prodigy 40 points

When VAC is unplugged, the conversion time 1.58ms.

How can I confirm the conversion time of 50us?

0 Ethan Galloway 2 months ago in reply to Marco Liu

TI__Mastermind 31035 points

Hello Marco,

50µs is the time for reverse mode to start operating. The time for the system voltage to rise up to VSYS_REV will depend on a wide variety of factors.

Marco Liu said:
How can I confirm the conversion time of 50us?

I'm not sure what you mean by this question. I measured the response time of 50µs by measuring the time between the charger switch nodes turning-off from VAC falling to ACUV and the switch-nodes switching again when reverse mode was activated.

Let me know if this answers your question.

Best Regards,
Ethan Galloway

0 Marco Liu 2 months ago in reply to Ethan Galloway

Prodigy 40 points

Can you kindly tell me which two points of EVM did you measure to get 50us?

0 Ethan Galloway 2 months ago in reply to Marco Liu

TI__Mastermind 31035 points

Hello Marco,

Here's an app note that shows the results of auto reverse mode: https://www.ti.com/lit/an/sluab05/sluab05.pdf

I measure the time for the switch node (SW2) to stop switching (powering forward mode) to start switching again (powering reverse mode).

Best Regards,
Ethan Galloway

Power management

Power management forum

BQ25750: auto reverse mode will still function within 50us, from charge mode to discharge mode?