TPS62740: TPS62740 VSEL Pins

Mesut TOPUZLU

Intellectual 690 points

Part Number: TPS62740

Hi.

Can I control voltage selector pins (VSEL) with MCU connection directly?

I want to change VOUT voltage level with main MCU that connected to VOUT.

over 7 years ago

0 Chris Glaser over 7 years ago

TI__Guru**** 150790 points

Hi Mesut,

Yes, you can. The VSEL pins are just digital inputs that need a logic high or low. Be sure that the signals driving the VSEL pins do not go high-Z, or else you may need to add a pull-up/down to keep them in a known state.

0 Mesut TOPUZLU over 7 years ago in reply to Chris Glaser

Intellectual 690 points

Hi Chris
You said that;

"You should pull down or pull up VSEL pins because it must stay known state, and than you control it via MCU"
Am I right?
if I did'nt misunderstand you how value of pull up/down resistors?

0 Chris Glaser over 7 years ago in reply to Mesut TOPUZLU

TI__Guru**** 150790 points

Hi Mesut,

It is common that, before power on, an MCU's pins are not in a defined state. If this is the case, you need a pull up/down. This app note calculates the maximum value of such a resistor: www.ti.com/.../slva485.pdf

The VSEL pins should always be terminated high or low.

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TPS62740: TPS62740 VSEL Pins