BQ77910A ON/OFF SWITCH

KIM DOSOEK

Prodigy 100 points

Other Parts Discussed in Thread: BQ77910A

hello!

I am an engineer for batterypack. I want to add a switch for turning on/off the bq77910a power.

I want to turn off the power of battery pack when not use, to save the energy of battery pack.

Is it possible?

Please tell me about how to configure if possible.

Thanks..

over 10 years ago

0 WM5295 over 10 years ago

TI__Guru 54715 points

If you short the thermistor (TS) and meet the detection timing it will shut down if the CHGST is low. To wake it up, take CHGST high until it is awake. So it would take 2 switches.

0 KIM DOSOEK over 10 years ago in reply to WM5295

Prodigy 100 points

I want to turn off the power immediately but It didn't turn off immediately that you taught me.

What is the way to turn off the power immediately when turning off the switch?

Is it possible?

0 WM5295 over 10 years ago in reply to KIM DOSOEK

TI__Guru 54715 points

The bq77910A does not have an on/off input control. It will turn off with appropriatly enabled fault conditions as described in the datasheet. The shorted thermistor is one of these methods. To get an immediate turn off, you might consider if it is possible to safely reset the device in your system as described in http://e2e.ti.com/support/power_management/battery_management/w/design_notes/1450.bq77910-reset-how-can-i-recover-from-a-permanent-fail.aspx You must have control of CHGST of course to wake the part/pack again.

Power management

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BQ77910A ON/OFF SWITCH