MP2672AGD: Not charging battery

[maan.gagandeep]

Hey,

I have made a charger using MP2672, schematic is according to the datasheet.

its standalone, without any mcu communication.

it does detect the battery and shows its charging (status led solid) however its not pulling any load (0.08A) and not even getting slightly warm.

when I disconnect the battery, the status pin blinks

battery is 2s li-on at 7.14v.

when I check the voltage at chargers terminal without attaching the battery, it shows 8.something volts, when I check with battery connected to the charger terminal, is shows 7.14v (battery voltage)

resisters are setup for 2A

ISET is 6k (2x12k in parallel)

vLIM is 23.2k to vbus and 10k gnd

the inductor is CDRH104R-1R5NC

thanks!

[todelbru]

I hear you, having struggled for the past months, it is tricky to get this charger working. What about VLIM? (I can’t see it on your schematic). If you don’t set VLIM to something like 2.5V or 3V the charging will not turn on.

And what do you see on VBUS? And can you see that the switching regulator is working to generate something like 8.5V?

Compare with my schematic at MP2672 VBUS oscillations - #7 by todelbru

[maan.gagandeep]

hey, thanks for replaying.

VLIM is set to 4v (23.2k to vbus, 10k to gnd)
thank you for this input, I will test with a lower value vlim

I measured the voltage at Battery terminals without connecting the battery , it shows 8.9v.

with battery connected, its show’s battery voltage (7.14v)

vbus is 5.10 v

my schematic is according to the data sheet refecrence design (standalone mode)

thanks again, I will test with lowering my VLIM to 2.5v , check and update

[maan.gagandeep]

hey, I tried with vlim at 2.4v , still the same behaviour.

anyone from MP team? this is a very weird issue, the schematic is according to the reference design shared in the official data sheet.