BQ25120A: inductor alternative for bq25120

igor zov

Part Number: BQ25120A

I'm using BQ25120A with spec recommended 2.2uH inductor - GLFR1608T2R2M-LR.

It was chosen due to the smallest package size in recommended inductors list - 0603 - and sufficient current - 150mA.

It is nearing the EOL so needs a replacement.

It looks that CBMF1608T2R2M by TAIYO YUDEN would fit the bill. Can you please confirm this choice or suggest the alternative.

Thanks

Igor

over 5 years ago

0 Raheem over 5 years ago

TI__Mastermind 21590 points

Hello Igor,

What is your load current for your DCDC converter?

0 igor zov over 5 years ago in reply to Raheem

Prodigy 40 points

total consumption may get to 100mA

0 Raheem over 5 years ago in reply to igor zov

TI__Mastermind 21590 points

Hello Igor,

With 100mA load current, the inductor current could be as high as 230mA. Hence an inductor with higher max current will be needed.

Take a look at MBKK1608H2R2M. It has a higher DCR which might affect efficiency.

0 igor zov over 5 years ago in reply to Raheem

Prodigy 40 points

What current can 160mA inductor support - 70mA ?

0 igor zov over 5 years ago in reply to Raheem

Prodigy 40 points

Actually bq25120A spec claims up to 300mA with recommended inductor (160 mA) :

1 Features
1• Increases System Operation Time Between Charges
– Configurable 300-mA Buck Regulator (1.8-V Default)
– 700 nA (typical) Iq with Buck Converter Enabled (No Load)
– Configurable Load Switch or 100mA LDO Output (Load Switch by Default)
– Up to 300-mA Charge Current for FastCharging
– 0.5% Accurate Battery Voltage Regulation (Configurable from 3.6 V to 4.65 V in 10-mV Steps)
– Configurable Termination Current Down to 500 μA
– Simple Voltage Based Battery Monitor

0 Raheem over 5 years ago in reply to igor zov

TI__Mastermind 21590 points

Hello Igor,

This is correct that the BQ25120A buck can support up to 300mA load, you'll have to select the inductor with appropriate current rating for your application.

Take a look at equation 8 on page 28 of the datasheet shown below. You want the saturation current of the inductor to be higher than the maximum inductor current.

Power management

Power management forum

BQ25120A: inductor alternative for bq25120