IMP527
Application Information
Test Circuit
Figure 1
shows the IMP527 configured to drive an EL lamp,
represented as a 3nF capacitor.
ON = V
DD
R
EL
OFF = 0V
1
V
DD
R
SW
L
D
R
EL-OSC
V
A
V
B
GND
8
7
3nF
2
R
SW-OSC
3
C
S
6
5
+
V
DD
1N4148
4
L
X
0.1µF
1
C
S
0.1µF
100V
C
SW
*
0.1nF
–
IMP527
Note:
1. Larger values may be required depending upon supply impedance.
* Optional
527_03.eps
Figure 1. Test Circuit
Table 1. V
IN
= 1.5V
Component
R
SW
R
EL
L
C
S
D
C
SW
Connections
V
DD
, R
SW-OSC
V
DD
, R
EL-OSC
V
DD
, L
X2
C
S
, GND
L
X
, C
S
R
SW-OSC
, GND
Value
1MΩ
1MΩ
330µH
2
0.1µF/100V
1N4148
0.1nF
Description
Boost converter oscillator bias resistor
EL lamp driver oscillator bias resistor
Boost converter inductor
Boost converter storage capacitor
Switching diode
Noise-suppression capacitor (optional)
Notes. 2. Murata LQH4N331K04 (8.2
Ω
max. DCR)
Table 2. V
IN
= 0.9V
Component
R
SW
R
EL
L
C
S
D
C
SW
Connections
V
DD
, R
SW-OSC
V
DD
, R
EL-OSC
V
DD
, L
X3
C
S
, GND
L
X
, C
S
R
SW-OSC
, GND
Value
1MΩ
2.62MΩ
680µH
3
Description
Boost converter oscillator bias resistor
EL lamp driver oscillator bias resistor
Boost converter inductor
Boost converter storage capacitor
Switching diode
Noise-suppression capacitor (optional)
0.1µF/100V
1N4148
0.1nF
Notes. 3. Coilcraft DS1608C-684 (2.2
Ω
max. DCR)
© 2000 IMP, Inc.
Electroluminescent Lamp Driver
5
IMP [ IMP, INC ]
