PIC12F683 DS41211D-page 2 © 2007 Microchip Technology Inc. 8-Pin Diagram (PDIP, SOIC) 8-Pin Diagram (DFN) 8-Pin Diagram (DFN-S) TABLE 1: 8-PIN SUMMARY. To obtain the most up-to-date version of this data sheet, please register at our Worldwide Web site at: http://www.microchip.com. INEMO inertial module: 3D accelerometer and 3D gyroscope Datasheet -production data already used for the production of micromachined Features. Datasheet search engine for Electronic Components and Semiconductors, integrated circuits, diodes and other semiconductors.

I've been having slow startup problems with my 12F629 and 12F683 32.768hz crystal clocked pics. I used the crystal recommended in the Midrange Reference Manual DS33023A (Epson C-001R32.768K) and from the recommend capacitors range (68-100pf) I started with 68pf. It takes several seconds for the oscillator to stabilize. I tried the hign end of the range, and it never starts with a 100pf cap. So reading the Basic PicMicro Oscillator Design document AN849, it indicates to use a 33pf cap, which works much better. In fact I've found it works with caps down to 5pf. While AN849 is probably the definitive document on this stuff, I found it hard to apply in practice with my limited equipment and experience.

I'm curious to know what others have found to be the best value to use with similar setups at 32Khz. AVR's have a calibration byte for the internal oscilator don't pic's as well? I know it's temperature dependant, but manual calibration should get you within 1% at operating temperature. If you're using a low frequency crystal though I'm asuming you're doing some kind of real time clock function on the PIC?

For that you would need a crystal, or an external oscilator refrence from a crystal driven source. Why is the stabilization time so important?

I'd figure it would take a while for a low frequency oscillator to stabilize because noise is more prevalent in the lower frequency range. If you're just trying to keep current down use a full speed crystal and just utilize the sleep modes. What are your exact timeing and power requirements?

I must not have said that right. Input A Radio With Guts Zip here. As for accuracy, I was just replying to mramos1. For my purposes, I can work around the accuracy. I'm really only using the crystal to get the lowest possible current draw. Part of what prompted me to ask was that the current draw is higher during startup before the pic is happy with the crystal.