> If you have 2 additional I/O lines on the PIC, use one to detect the power failure and the other to switch on a LED ( to drain the cap) AFTER you finish writing to the EEPROM. Pailoor P.S. Post rejection has started. > Lynx {Glenn Jones} wrote: > > > Hello all, > > I have a circuit (it contains a pic) which has a couple of rather > > large > > aluminum electrolytic capacitors (2200uF) as supply filters. the > > problem > > is that when the circuit is turned off, the charge takes a little > > while to > > dissipate (i have a power on led in series with a 1K resistor across > > > the > > supply lines) and while its dissipating, the pic among other things > is > > > > still funtioning. I am worred that the pic might end up in one of my > > > routines which, for example writes to an I2C EEPROM, and corrupt the > > > data > > there. so what i need is a way to disipate the capacitor reletively > > quickly after power down. I was thinking of putting a diode in > paralel > > in > > the wrong direction (anode to gnd, cathode to vcc) but i dont think > > this > > will work, since the charge in the capacitor is polarized. I hope > > someone > > has an idea.. thanks agian > > > > -------------------------- > > --------------------------------------------------- > > A member of the PI-100 Club: > > 3.1415926535897932384626433832795028841971693993751 > > 058209749445923078164062862089986280348253421170679 Chip Technologies Microchip Design Consultant No. 70, 9th Main Road, Mathikere, Bangalore - 560 054. INDIA Tel : +91-80-3362807 Fax : +91-80-3369451 Email : chiptech@vsnl.com Webpage : http://business.vsnl.com/chiptech