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A battery replacement soldering kit
Juice is a battery replacement kit for use in prototyping and when you're out of battery juice.
It comes as a single panel that breaks out to six assembled batteries (two AAs, two AAAs, one CR2032, and one A23). The main board can be configured to provide three fixed voltages (1.5V, 3V, or 4.5V) or an adjustable voltage output. The kit comes with a cardboard enclosure that can be cut, folded, and glued to create a lovely tuck-box for storing the assembled pieces.
Juice was project #12 of the Boldport Club.
Here is a list of components that come with the kit
1x Micro USB connector, Multicomp MC001009
1x Adjustable LDO regulator, ST LDFPT-TR
1x 20KΩ trimmer, Bourns TC33X-2-203E
2x 1KΩ resistor, Multicomp MF25 1K
1x 3.3KΩ resistor, Multicomp MF25 3K3
1x 5.6KΩ resistor, Multicomp MF25 5K6
2x 1.2KΩ resistor, Multicomp MF25 1K2
2x 2.2µF ceramic capacitor, Multicomp MCMLR50V225MY5V
1x 10µF electrolytic capacitor, Multicomp MCMR35V106M4X7
1x 6-contact long pin header, Samtec TSW-106-22-T-S
1x 3-contact 2.54 mm SMD header, Samtec TSM-103-01-T-SH
1x Orange LED, Kingbright L-9294SECK
An infographic with assembly information is provided available here. A few things to note:
When The Chooser isn't connected the output voltage will be the same as the input voltage. This could cause problems when removing The Chooser while having a high voltage on the input and the target device can't handle it.
The USB socket is hard to solder. To make it easier, break off the three middle pins (they're not connected on the circuit anyway) and that makes soldering easier. The USB socket is optional, as it is only an alternative power source, so if it's not soldered on, it's OK.
To avoid power contention never power the board through the USB and the side contacts.
Most components have an alternative SMD footprint so one could build the circuit with SMD components instead of the ones supplied.