Problem running from a 3v battery

[tbirchall]

I'm using a 16F628A which I believe should run as low as 2 volts. It works just fine from batteries providing just under 6 volts but not from 3 volts. The setup is a simple button to INT that triggers an LED to blink. Bypassing the chip and powering the LED (though the resistor) lights up the LED just fine. I figured maybe the battery didn't have enough juice, so I connected the circuit to a line power supply set at 3 volts and it didn't work. Me thinks I'm missing something here...

Thanks,
Tom

[mister_e]

Did you also tried with the LF serie???

Did you try to disable the Brown-Out detect fuse???

F serie are suppose to work @ 3v under 10MHZ. See the Voltage-Frequency graph at the end of the datasheet.

I have a load (>10 000 units) of these F serie and LF serie on the market now running with a pair of AAA cells. No problem with them... as now...

[Bob_W]

Do you have the BOREN configuration bit set? If so, it looks like you'll be in brown out reset if you are under 3.65-4.00 volts.

[Bruce]

I think Bob has hit on the problem. You'll need to disable BOR, and stay below 10MHz oscillator frequency to run this PIC at 3V.

[Bob_W]

Actually, I think it was race to the finish between me and mister_e based on the timestamps. He said it also..... He must type faster than me : )

[mister_e]

hehe i had this impression of 'already said before' or "DEJA VUE' depending french ore english version you want to have.

Now that we are 3 with the same version/results... i must be true