IMP560
Enable/Disable Operation
Figure 3
shows the IMP560 can be enabled via a logic gate that con-
nects R
SW
to V
DD
, and disabled by connecting it to ground. R
EL
may
be connected either to V
DD
or to the gate.
CMOS
Gate
Enable/Disable Table
R
SW
Connection
V
DD
Ground
IMP560 State
Enabled
Disabled
ON = V
DD
OFF = 0V
R
EL
1
V
DD
L
1
R
SW
R
EL-OSC
V
A
V
B
GND
8
7
EL lamp
2
R
SW-OSC
3
C
S
6
5
+
V
IN
1N4148
4
L
X
0.1µF
2
15V
0.1µF
100V
–
IMP560
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5
Ω
)
2. Larger values may be required depending upon supply impedance.
560_11.eps
Figure 3. Enable/Disable Operation
Dual Supply Operation with 1.5V Battery
The IMP560 can also be operate from a single battery cell when a
regulated voltage higher than 2.0V is also available. The dual
supply configuration, shown in
Figure 4,
uses the regulated
voltage to operate the IMP560 while the energy for the high-
voltage boost circuit comes from the battery. The current to run
the internal logic is typically 420µA.
The circuit of
Figure 4
can also be used with batteries that exceed
6.0V as long as V
DD
does not exceed 6.5V.
Regulated Voltage
(2.0V to 6.5V)
ON = V
DD
R
EL
OFF = 0V
1
V
DD
R
SW
L
R
EL-OSC
V
A
V
B
GND
8
7
EL lamp
2
R
SW-OSC
3
C
S
6
5
Battery
Voltage
V
IN
+
–
0.1µF
*
1N4148
4
L
X
C
S
0.1µF
100V
IMP560
* Larger values may be required
depending upon supply impedance
560_12.eps
Figure 4. Dual Supply Operation with High Battery Voltages
6
408-432-9100/www.impweb.com
© 2000 IMP, Inc.
IMP [ IMP, INC ]
