Excessively high output error (4%) with NPM1100

[peterqu94305]

Hello,

We have designed a product with NPM1100.  With the NPM1100 set to output voltage of 3.0, we have measured the output across multiple devices to be in the 3.1 to 3.15V range.  This is an approximately 4% error on the output. 

Our questions are:

1. What is the expected output accuracy of NPM1100?
2. What is the expected accuracy of the charging termination voltage?  If the charging termination voltage has the same level of large error, then we have genuine concern about whether using NPM1100 can lead to potential safety hazard with lithium-ion battery.

Our configuration is as follows.

1. Micro USB input
2. Rechargeable lithium ion 80mAH
3. Output configured to 3.0V

Thank you,

Peter

[Dom O]

Hi Peter - I'm getting the same result. 3.113V to 3.114V output, across GND and VOUTB, on my nPM1100-EK, with or without a 20mA load, with or without USB charging connected.

Checked with 2 different voltmeters, one calibrated and within 1mV agreement with each other.

Also the following values (typically about 3.5% high across all values):

Set Voltage	Measured Voltage
3.0V	3.113V
2.7V	2.801V
2.1V	2.176V
1.8V	1.863V