D340B Datasheet, PDF (7/9 Pages) List of Unclassifed Manufacturers – Electroluminescent Lamp Driver IC

III. Two-Level Dimming
Toggle switching between two different EL lamp brightness levels may be achieved with the following
circuit. When DIM is low, the external pnp transistor is saturated and the EL lamp runs at full brightness.
When DIM is high, the external pnp turns off and the 47W resistor reduces the voltage at (V+) and dims the
EL lamp.
IV. Automatic Turn-Off After Short Time Delay
It is sometimes desirable for the EL lamp to turn off automatically after a few seconds of operation. Typically, a
mechanical switch pulls E’ low to initially turn on the device. When the switch is released, Cdelay keeps the D340B
operating for a short period before turning off. The following table shows typical delay on-times.
C delay (uF)
5
7
10
15
20
Vbat
1.5V
1.8 sec
2.3 sec
5.6 sec
5.9 sec
7.7 sec
3.0V
2.4 sec
3.1 sec
7.8 sec
9.0 sec
11.2 sec
Vbat
1.0uF
1MOhm
1 V+
Cdelay
2 E’
L+ 8
VOUT 7
3 GND
L- 6
4 N/C
D340B
N/C 5
EELL LLaammpp
5.6 mH
7