D372A Datasheet, PDF (10/12 Pages) List of Unclassifed Manufacturers – Electroluminescent Lamp Driver IC

III. Split Voltage Supply
A split supply voltage may also be used to drive the D372. To operate the on-chip logic, a regulated voltage supply (V+)
ranging from 2.0V to 6.5V is applied. To supply the D372 with the necessary power to drive an EL lamp, another supply
voltage (Vbat) is applied to the inductor. The voltage range of Vbat is determined by the following conditions: driver
application, lamp size, inductor selection, and voltage and current limitations.
Two different examples of the split supply are shown below. The first example shows a regulated 3.0V applied to the
V+ pin, and a Vbat voltage that may range from 2.7V to 4.5V. The enable voltage is in the range of 2.0V to 3.0V. This
is a typical setup used in cell phone applications.
V+
Regulated 3.0 V
0.1 µF
2.0V - 3.0V on
0 V off
1 V+
CLF
2 CLF
Rd
Rd 10
EL2 9
3 CHF
CHF
4E
EL1 8
Cs
Cs 7
5 GND
L+ 6
L
D372A
EL Lamp
Vbat
2.7 V - 4.5 V
The second example shows that V+ may range from 2.0V to 6.5V, and the Vbat voltage may be as high as 12.0V.
The enable voltage is in the range of 2.0V to V+. This is useful in many high voltage applications.
V+
2.0 V - 6.5 V
0.1 µF
2.0V - V+ on
0V off
1 V+
CLF
2 CLF
Rd
Rd 10
EL2 9
3 CHF
CHF
4E
EL1 8
Cs
Cs 7
5 GND
L+ 6
L
D372A
EL Lamp
Vbat
12.0 V
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