Gabriel Paubert wrote: > However, you want to have power for longer than this device. The PowerStor > series from Cooper Bussmann might fit your bill (1kHz ESR down to 0.2 Ohms), > but they are neither cheap nor very small (especially the lowest ESR PA > series): >
I found the TPL-0.5/8X12F [1] boost supercap around 1am this morning. It's 2.7V, 0.5F, and has a 1.5ohm DC ESR in a 8mm dia by 12mm long package. It's still a little too big, but there is a smaller version, the TPL-0.5/6X9F that isn't UL approved yet. Same characteristics as above, except that it has a 2.2 ohm DC ESR, in a 6.3mm dia by 9mm long package. Sweet! I have an email out to those guys about max current draw and eta, we'll see. With some hacking, I can use one of the pic's output pins to provide it power at 2.3V, and then I can shut off the circuit when I don't need it. Otherwise, I may just do a diode drop... Now, my concern is recharging interval for the supercap. I may have to do a current-limiting resistor, not sure yet. thx, Jason. [1] - http://www.tecategroup.com/store/index.php?main_page=product_info&cPath=18_19_44&products_id=84 _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user