The LiPo balancer cell acts like a big and very accurate zener diode; when the cell voltage is under a threshold fixed by the user the system is in “idle state” and watch only for the voltage with a equivalent resistance of some KOhm and a negligible current shunt. When the voltage reaches the threshold the balancer element will start to shunt current from the cell with an internal power resistor: the amount of current sunk by the element is proportional to the cell overvoltage with respect the user “safe” threshold.
LiPo Balancer Element: [Link]
The MAX6953 from Dallas Maxim is a compact cathode-row display driver that interfaces a microprocessor (like PIC or AVR) to four 5×7 dot matrix LED display trough an I2C compatible serial interface. The Max chip includes some nice features like:
- low-power shutdown mode
- segment blinking
- test mode that forces all LEDs on
- 16-Step digital brightness control
This project can be considered both a led matrix controller and a development board for MAX6953. The project presents only the max6953 and the led matrix, if you want it to display anything, you’ll also need to stick a microcontroller in there and write some code. You might want to check this other article 50×7 LED Matrix which has everything included.
MAX6953 LED Matrix or development board: [Link]