Carregador de Baterias NIMH AA Pela USB do Micro

Cell Type	Charge Time
700mAh NiCd	1.5h
1100mAh NiCd	2.5h
1600mAh NiMH	3.5h
2000mAh NiMH	4.5h
2500mAh NiMH	5.5h

retirado e editado de:http://www.stefanv.com/electronics/usb_charger.html

Part	Description
R1	56kΩ ¼W, 5% resistor
R2	27kΩ ¼W, 5% resistor
R3	22kΩ ¼W, 5% resistor
R4	47kΩ ¼W, 5% resistor
R5	750Ω ¼W, 5% resistor
R6	220Ω ¼W, resistor
TR1	10kΩ @ 25°C thermistor, approx. 3.7%/C° NTC Radio Shack #271-110 (discontinued†)
C1	0.1µF 10V capacitor
Q1	TIP32C PNP transistor, TO-220 case
Z1	LM393 dual voltage comparator IC, DIP
LED1	Red, green, or yellow LED, 10mA
Other	2-cell AA battery holder USB cable Small heatsink

Part	Alternative Resistor Values to use with Vishay #2381 640 54103 Thermistor
R1	82kΩ ¼W, 5% resistor
R2	33kΩ ¼W, 5% resistor
R3	27kΩ ¼W, 5% resistor
R4	39kΩ ¼W, 5% resistor