TPS61021A: EN Logic Low threshold

K.Yaita

Part Number: TPS61021A

Hi Team,

My customer considers to use TPS61021A and controlls EN pin by MCU GPIO output.
I would like to ask about the following "EN Logic Low threshold".

The following is VOL specification of GPIO and shows VOL_max=0.6V.
Is it possible to connect the following GPIO output to EN pin of TPS61021A directly?

If the answer is no, should we put pull-down resistor?
If so is there recommended value of pull-down resisotr?

Best Regards,
Yaita / Japan disty

over 7 years ago

0 Jing Ji over 7 years ago

TI__Intellectual 2655 points

Hi Yaita,

You can not connect GPIO to EN directly.

I suggest

1 MCU Vcc=3V, which makes VOH(min)=2.4V

2 use a resistor divider to control EN pin, like below picture.

0 Helen chen over 7 years ago

TI__Mastermind 40080 points

Hi Yaita_san,

The answer is no. In order to shutdown TPS61021, the EN pin low voltage should be lower than 0.36V or (0.3*Vin) when Vin<1.2V. So you need to add pull down resistor. The resistor value can be lower than 10K.

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TPS61021A: EN Logic Low threshold