UC2906: Sinking problem

Steve Kow

Part Number: UC2906

I have a UC2906N chip connected to a series pass PNP transistor (TO220 TIP32B) via pins 16 and 15. For some reason if we short the base and emitter the driver circuit starts. I don’t know why this is the series pass element seems to be ok. What are your recommendations.

over 2 years ago

0 Jing Zou over 2 years ago

TI__Mastermind 20570 points

Hi Steve,

Due to US holidays, a team member will get back to you in the week of Jan 9.

At the meantime, we recommend to use the app note below for charging lead acid battery with our Li-ion battery charger as UC2906 is a legacy device, there is very limited support on this device.

https://www.ti.com/lit/an/slua992/slua992.pdf?ts=1671813999032&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fen-us%252Fdocs%252Funiversalsearch.tsp%253FlangPref%253Den-US%2526searchTerm%253Dbq24610%2Blead%2Bacid%2526nr%253D62

0 Bill Johns over 2 years ago in reply to Jing Zou

TI__Guru* 75606 points

Hi Steve

You are testing with a bate to emitter short applied to the pass transistor, what is the requirement or problem you are investigating?

The drive circuit starts in this condition, do you see output current increase?

Do you have a schematic of your design that you can share?

Power management

Power management forum

UC2906: Sinking problem