TLV62130: Dividing EN Voltage

Kazuki-San,

Yes you can use resistor divider at EN pin but if you are looking to enable the TLV62130 at a precise input voltage, then the  TPS62147/8 (2A) or TPS62135/6 (4A) is a good alternative if you want to turn on the IC at a precise input voltage. The EN hi and lo thresholds are tight and that will help you have more control on the precise trigger voltage.

Thanks,

Amod

Hi Amod-san,

Thank you so much for your suggestion!

Could you please check the max. and typ. values of high level EN threshold voltage for TPS62130 and TPS62147/8 respectively?

Regards,

Itoh

Itoh-san,

For TPS62130, the max EN VH and min EN VL is not present in the datasheet and internal system. This device has the other thresholds specified in the datasheet. For registering logic HI at EN, you need to ensure you are higher than 0.9V and to register logic low ensure you are below 0.3V.

The TPS62147/8 has precise EN feature that allows more control on trigger point. EN thresholds are specified in datasheet as well.

Hope this helps!

Thanks,

Amod

Thanks for your reply.

Are TPS62130 specifications for EN pin equal to that of TLV62130?

We use TLV62130, so we want to know specifications of TLV62130.

Anyway, regarding resistor divider at EN pin, it ok to use resister value for the divider from kOhms - 10kOhms?

Moreover, we consider to use Reset IC in order to delay(about:7sec) the detection of En pin.

What Reset IC do you recommend?

If there are, please give us the information.

Regards,

Tsujita

Thanks for your kind reply.

We confirmed the following.

Case1：After Vin is stable in 5V, we supply EN pin from 0V to 5V (increasing by 0.5V/s).

We confirmed that Vout outputed when EN pin was about 0.64V. And we confirmed that Vout was good.

Case2：EN pin is connected with Vin, and Vin supply from 0V to 5V (increasing by 0.5V/s).

We confirmed that Vout outputed when EN pin was about 2.96V. And we confirmed that Vout dropped like 2ch of the following figure.

1ch:EN,2ch:Vout

What the reason is the behavior of Case1 and Case2?

Regard,

Tsujita

In case 1, EN HI threshold was hit and the IC turned on and regulated. In case 2, since VIN and EN are connected, both EN HI threshold and VIN UVLO threshold needs to be exceeded (around 2.8V or higher) for the IC to turn on and regulate. The scopeshot you attached is quite small but it looks like there is 400mV or so ripple on VIN which carries over to VIN. The rising/falling hysteresis on both these pins for UVLO and EN is around 200mV so it can cause issues. Please confirm how much ripple you have on VIN and see if reducing it makes any difference.

Thanks,
Amod