topic Re: MC34674 soldering help in 8-bit Microcontrollers

MC34674 soldering help

mimco — Wed, 11 Mar 2009 20:04:20 GMT

Hi,

I know that this theme is not about MCU, but I don't know to which group belongs. I need hand-solder Lion charger MC34674, but I don't know how. I try solder 3 pieces but unsuccesfully. When I complete 2 PCB with this IC, after supply voltage and battery connection, the one LED was turned on, VBAT was 3.78V (after battery disconnect was this voltage around 2.5V), but Vref was still 0V and I don't know if this was caused unsuccesfull soldering or other error. Please any idea how proprely solder this IC?

Thanks

PS: I'm sorry for my poor english.

Re: MC34674 soldering help

MrBean — Fri, 13 Mar 2009 19:17:44 GMT

Looks like a DFN8 with exposed-die-pad. (pad in the middle of the package))

Die pad is used to cool the device, and MUST be connected to ground.

Have you soldered the die pad ?

Message Edited by MrBean on 2009-03-13 13:18 01:18 PM

Re: MC34674 soldering help

mimco — Mon, 23 Mar 2009 02:17:20 GMT

Hi MrBean,
thank you for your answer. Yes the package looks the same like the DFN8 one. I've tried to solder EPAD to the ground but I don't know if I've succeded. I'm not sure how to test if it's done right. I've used different circuit instead after few failed attempts but I would like to try it again sometimes. Thanks

Best regards mimco