nPM2100 passthrough

[Nick_RA]

Can you clarify, is it possible for the nPM2100 to set Vout < Vbat I.e. 1.8v out with 3v battery? The behaviour of the EV kit suggests not...

The datasheet isn't really that clear: "It features one boost regulator that supplies 1.8 V to 3.3 V output, from input voltages of 0.7 V to 3.4 V. Supported batteries include any battery that operates within the input voltage range of nPM2100." 

Thanks

[Asbjørn]

Hello Nick,

For the BOOST pass-through mode, Vbat needs to be 100mV above the target Vout.

You can run the BOOST from 3V and have Vout set to 1.8V.

Maybe I'm misunderstanding you here now, so let me know if this wasn't the question you asked.

Best regards

Asbjørn

[Nick_RA]

I guess a better was to phrase my question: Is the switching regulator BOOST only rather than BUCK/BOOST?

When I set up the EV kit with PowerUP I couldn't set Vout less than Vbatt. I initially thought the EV kit may have been faulty but I bought a 2nd one to verify.

By the way, I don't mean using the LDO to drop VOUT down to 1.8v when using 3V battery.

[Audun]

Hi Nick_RA 

>I guess a better was to phrase my question: Is the switching regulator BOOST only rather than BUCK/BOOST?

Yes, the nPM2100 regulator is a BOOST only. When VOUT is set to lower than VBAT, it will pass VBAT directly to VOUT without regulation.

As you mention, there is an LDO available also, which would be the only way for nPM2100 to reduce VBAT voltage.

Best regards,

Audun