| Uninterruptible
Power supply (UPS)
By Ibrahim Kamal
28/02/08
DANGER: THIS CIRCUIT CONNECTS
TO 220 V! |
Brief
Circuit explanation:
This circuit
will provide electric power from a backup battery when AC power
is cut, always providing a clean 5V power supply for sensitive
equipment like microcontrollers and logic circuits.
The value of C1 is to be higher than 220 uF. the bigger the capacitance
of this capacitor, the more power you can deliver to your circuits.
The 9.6 NiMh Battery can be replaced with any equivalent battery
whose voltage is more than 7.5V.
A charger can be constantly connected to the battery from the
same 220V source as the rest of the circuit, but depending on
the battery and charger type, this procedure can shorten its life.
For a clean transition from AC to Battery operation, especially
with microcontrollers, use 10nF decoupling capacitors (ceramic
capacitors) as near as possible from the concerned IC.
Any questions? find
answers or ask your questions in ikalogic forum |
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