RTC+SuperCap+7805 I2C module
author: Heisenbug
2 layer board of 1.04 x 1.04 inches (26.3 x 26.4 mm)
Uploaded:
December 17, 2014
Shared:
March 20, 2015
Total Price:
$5.35
$5.35 / set of 3; but you can now get the new smaller version here for $4.50
Designed more for vertical use, e.g. right-angle 9pin header plugged into a breadboard.
DS1337s on top, Supercap (I chose 1.5F) and 78L05 (SOIC version 5-volt regulator) on bottom, and one or a pair of [low-Vf] diodes makes for a batteryless clock module that will happily keep time with monthly charging, on anything from 7~18v [using regulator] or can be run direct on 1.8-5v.
Don’t forget to install the jumper-wire, and charge session[s] should total 24-48 hours per month for better results with high-ESR supercaps.
The regulator can also power other small circuitry; just keep in mind power dissipation and current rating (~1W or 100mA).
Uploaded [originally] 10/20/2014 21:42.
$5.35 / set of 3; but you can now get the new smaller version here for $4.50
Designed more for vertical use, e.g. right-angle 9pin header plugged into a breadboard.
DS1337s on top, Supercap (I chose 1.5F) and 78L05 (SOIC version 5-volt regulator) on bottom, and one or a pair of [low-Vf] diodes makes for a batteryless clock module that will happily keep time with monthly charging, on anything from 7~18v [using regulator] or can be run direct on 1.8-5v.
Don’t forget to install the jumper-wire, and charge session[s] should total 24-48 hours per month for better results with high-ESR supercaps.
The regulator can also power other small circuitry; just keep in mind power dissipation and current rating (~1W or 100mA).
Uploaded [originally] 10/20/2014 21:42.
