NiMH Battery Board

The PPA NiMH battery board is designed to work in concert with the PPA v1 Amplifier Board. It charges the cells while the wall power supply is plugged in, and it powers the amp when the wall supply is removed.

While it was designed with the PPA amp's needs in mind, it doesn't depend on the PPA board. You can use it to power other circuits.

Specs:

• 6.3 in. × 3.925 in. board (Eurocard size, 160mm × 100mm)

• Uses plastic PC-mount battery holders to hold up to 18×AAA or 10×AA

• Reverse power supply voltage protection

• Uses the On Semiconductor MC3334x charge controller chip to ensure safe and effective fast charging

• Fast-charges cells in as little as one hour, followed by a trickle charging step to top cells off and maintain charge

• Full charge detected using the -ΔV method

• Backup fast charge termination based on charge time or pack temperature

• A simpler trickle-only charge arrangement is possible

• Indicator LED to distinguish between fast and trickle-charging modes

Where to Next?

View or Download the Schematic (ExpressPCB format)
View or Download the PCB Layout (ExpressPCB format)
Part Lists
Checklist
Part Selection Guide
Configuration Calculator
Step-by-Step Assembly Guide
Theory of Operation
Helpful Links