IMP527
Test Circuit
Figure 1 shows the IMP527 configured to drive an EL lamp,
represented as a 3nF capacitor.
ON = VDD
OFF = 0V
Application Information
REL
1 VDD
REL-OSC 8
RSW
L
2 RSW-OSC
VA 7
D
3nF
3 CS
VB 6
+
VDD –
1N4148
0.1µF1
CS
0.1µF
100V
4 LX
GND 5
CSW*
0.1nF
IMP527
Note:
1. Larger values may be required depending upon supply impedance.
* Optional
Figure 1. Test Circuit
Table 1. VIN = 1.5V
Component
Connections
RSW
VDD, RSW-OSC
REL
VDD, REL-OSC
L
VDD, LX2
CS
CS, GND
D
LX, CS
CSW
RSW-OSC, GND
Notes. 2. Murata LQH4N331K04 (8.2Ω max. DCR)
Value
1MΩ
1MΩ
330µH2
0.1µF/100V
1N4148
0.1nF
527_03.eps
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)
Table 2. VIN = 0.9V
Component
RSW
REL
L
CS
D
CSW
Connections
VDD, RSW-OSC
VDD, REL-OSC
VDD, LX3
CS, GND
LX, CS
RSW-OSC, GND
Notes. 3. Coilcraft DS1608C-684 (2.2Ω max. DCR)
© 2000 IMP, Inc.
Value
1MΩ
2.62MΩ
680µH3
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)
Electroluminescent Lamp Driver
5