Slow output rise time

Posted by: zedman on 03/20/2009

Hi,

I've built the EP48 design, I would like to use it to power an MCU and an RF module.
The MCU boots up well, but the RF module unable to reset properly and unfortunatelly it doesn't have any reset input.
I think it's because of the slow rise time of the 12V which feeds an 5V regulator.

Is there any way to decrease rise time?

thanks
Zedman

Comments

When the EP 48 is power un, the rise time is about 10 ms. is this the time you mean? let us know
PI-Worf

Actually I am just guessing that could be the problem, from a battery or other power source the RF module boots up correctly.

We also have a PIC mcu on this board, that's able to boot up.

thanks,
Zedman

the RF module is a HopeRF RFM12B, the mcu is a PIC18F2321.