Perhaps of interest and perhaps on topic

I just opened up 3 different solar path lights.

1) $1.00 from dollar store   has 1 amorphous solar cell on glass (in circui=
t V =3D~ 1.3V in bright light), 1 IC (pn ANA618) w 4 leads  1 large button =
cell (the tag on the lamp says NiMh 1.2V/60mAh),  1 white LED, 1 inductor, =
 and a switch. At first I thought that the inductor was a resistor but that=
 did not make sense so I approached it with a magnet, not only was the magn=
et strongly attracted (not really proof) but the light got brighter - proof=
 to me.
This unit's tag says  from L'Image Home Products  made in China

2) $2.00 from orchard supply   has 4 small crystal solar cells potted in pl=
astic, 1 IC (pn 6N06) w 4 leads  1 aaa NiCd cell  1 white LED 1 inductor  a=
nd a CdS cell. same inductor story. This one blinks when the battery gets l=
ow.

3) $2.00 from orchard supply   - has 1 amorphous solar cell on glass (1.33 =
in circuit w bright light, 1 IC (pn 5252F) w 4 leads  1 aa NiCd cell  1 whi=
te LED 1 inductor. same inductor story.
Tag says made for Orchard Supply in China=20
The circuit in this one is as follows:
pin 1 of IC has Sol+
pin2 B+ and L
pin3 B-, Sol-, Led-
pin4 Led+, and L              =20

Can't find any such chips on Google. But if you could, it might be a good t=
hing for the solar guitar tuner, I bet (at least $0.25) the chip has a boos=
t current source that could be a voltage source with a bit of tweaking - di=
ode + cap  + Zener?. You could go to OSH for the chips and all for $2.=20

Note the NiMh button cell in #1  (a solution to some size objection to NiCd=
 s by the OP.)
Note - none of these have visable diodes in series w the solar cell -   and=
 the cell V was too low to allow one in #1 and #3 (1.3V in circuit, perhaps=
 a fet is used to block reverse current to the solar cell?

But

=20

Looking forward,
Al Shinn
--=20
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