Solar-cell NiCad Charger
by Tony van Roon
solar nicad charger


Parts List
R1 = 820K, 1%
R2 = 75K, 1%
R3 = 75K, 1%
R4 = 1M, 5%
D1 = 1N5117, Zener diode (or equiv.)
D2 = 1N5117, Zener diode (or equiv.)
L1 = 100uH, coil
U1 = MAX639, integrated circuit
C1 = 100uF/40V, Electrolytic capacitor
C2 = 50uF/16V, Electrolytic capacitor

Additional Notes
The MAX639 has its own current limitter build in, set for 200mA. Plenty! Make sure that the charging NiCads can handel the contineous current of 200mA, for example, NiCad battery packs of 1700+ mA used for R/C (Radio Control) cars and electric aircraft.
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