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VI. High EL Brightness Through Supply Voltage Doubling
An external voltage boost circuit may be used to increase the voltage supplied to the D365. In the following circuit, the
National Semiconductor LM2661 is used as a positive voltage doubler.
1
2
3
4
8
7
6
5
L+
VOUT
V+
GND
L-
CHF
E
L
D365
BASE
EL Lamp
CHF
capacitor
pnp transistor
V+
OFF
ON
LM 2661
Vin
SD
CAP+
GND
CAP-
V+
OSC
LV
OUT
1N5817
47uF
47uF
10uF
VII. EL Lamp Brightness Regulation
Regulating the DC supply input voltage to the D365 will result in a constant brightness level from the EL lamp,
regardless of battery voltage. In this example, a Micrel voltage regulator is used.
1
2
3
4
8
7
6
5
L+
VOUT
V+
GND
L-
CHF
E
L
D365
Vbat
BASE
EL Lamp
CHF
capacitor
0.1 µF
pnp transistor
V+
OFF
ON
1GND
2E
OUT
IN
4
3
MIC5203
E
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