TLV61225: Power management forum

Bryn Jones

Part Number: TLV61225
Other Parts Discussed in Thread: TPS61070,

I am using a TLV61225DCKR DC-DC in a 3V battery powered application to generate 3V3 from the battery until the battery gets to around 1.7V

The EN pin (Pin 6) is connected to the GPIO pin of a ST microcontroller running from the 3V battery and also has a 10K pulldown to GROUND.

The aim is to use the microcontroller to switch the DC-DC on and off as needed.

When the GPIO is not connected to the EN pin (track cut) and only the 10K is connected to GND the output of the TLV61225DCKR is not 0V but at 2.713V.

If the 10K is removed the output stays at 2.713V.

I cannot get the output of the DC-DC IC to go to 0V.

I have not tried shorting the EN pin to GROUND and will do that now.

Any ideas?

over 5 years ago

0 Jasper Li over 5 years ago

TI__Mastermind 46905 points

Hi Bryn,

the TLV61225 doesn't has disconnection feature, so the output voltage will be VIN-0.5V if the EN pin is zero. A device such as TPS61070 has such feature, so the output voltage will be zero at EN=L.

why do you want to have zero voltage at EN=L

0 Bryn Jones over 5 years ago in reply to Jasper Li

Prodigy 150 points

HI Jasper

Thank you for the feedback, I did find this comment but feel that for a battery powered DC-DC it is a very important feature (or lack there of) and would like to see this highlighted.

I am using the DC-DC to step up my CR2032 battery voltage to 3V3 for a OLED display and when I go into low power mode I shut down all my peripherals.

The design is to turn off the DC-DC so that it also goes into a lower power consumption mode.

The OLED displays also don't like to have their supply drop too low.

Let me check out the alternative you identified.

Hopefully it is a drop in for the current part.

Keep well