2000 IMP, Inc.
408-432-9100/www.impweb.com
1
IMP803
IMP803
P
OWER
M
ANAGEMENT
High-
High-
V
V
olt
olt
ag
ag
e EL Lam
e EL Lam
p Dr
p Dr
iv
iv
er
er
N GPS units/Pagers/Cellular phones
N PDAs/Handheld computers
N Safety illumination
N Portable instrumentation
N Battery-operated displays
N LCD modules
N Toys
N Low Power: 420A typical V
DD
current
N Wide operating voltage range - from 2.0V to 6.5V
N 180V peak-to-peak typical AC output voltage
N Large output load capability - drive lamps
with more than 30nF capacitance
N Adjustable output lamp frequency for control of
lamp color, lamp life, and power consumption
N Adjustable converter frequency to minimize
power consumption
N Device can be Enabled/Disabled
N Low quiescent current 20nA (disabled)
N High-Voltage CMOS Process
N MicroSO package option
Key Features
Applications
+
803_01.eps
V
DD
1
L
X
4
C
S
3
V
A
7
V
B
6
R
SW-OSC
2
Switch
Oscillator
Regulation
Control
IMP803
Bridge
Output
Driver
Q
Q
Q
V
REF
Lamp Drive
Oscillator
C
GND
5
R
EL-OSC
8
Q
The IMP803 is an Electroluminescent (EL) lamp driver with the four EL
lamp driving functions on-chip. These are the switch-mode power sup-
ply, its high-frequency oscillator, the high-voltage H-bridge lamp driver
and its low-frequency oscillator. The IMP803 drives EL lamps of up to
30nF capacitance to high brightness; EL lamps with capacitances greater
than 30nF can be driven, but will be lower in light output. The typical
regulated output voltage that is applied to the EL lamp is 180V peak-to-
peak. The circuit requires few external components, a single inductor,
single diode, two capacitors and three resistors. Two of these resistors
set the frequency for two internal oscillators.
The IMP803 operates over a 2.0V to 6.5V supply voltage range. A
regulated, low-power source can supply the low quiescent current of the
IMP803. The inductor may be driven from an independent, unregulated
supply voltage in dual supply applications.
An internal circuit shuts down the switching regulator when the lamp
drive voltage reaches 180V peak-to-peak. This conserves power and
extends battery life.
The IMP803 is available in MicroSO and SO-8 packages and in die or
wafer form.
Block Diagram
I M P 8 0 3
I M P 8 0 3
2
408-432-9100/www.impweb.com
2000 IMP, Inc.
Parameter
Symbol
Conditions
Min
Typ
Max
Units
ON-resistance of MOS Switch
R
DS(ON)
I = 100mA
3.5
8
Output Voltage Regulation
V
CS
V
DD
= 2.0 to 6.5V
80
90
100
V
Output Voltage Peak-to-peak (in regulation)
V
A
-V
B
V
DD
= 2.0 to 6.5V
160
180
200
V
Quiescent V
DD
Supply Current, Disabled
I
DDQ
V
RSW-OSC
< 100mV
20
200
nA
Input Current at V
DD
Pin
I
DD
V
DD
= 3.0V, See Figure 1
420
700
A
Input Current at V
DD
Pin
I
DD
V
DD
= 5.0V, See Figure 2
500
750
A
Input Current: I
DD
Plus Inductor Current
I
IN
V
DD
= 3.0V, See Figure 1
20
31
mA
Output Voltage at V
CS
V
CS
V
DD
= 3.0V, See Figure 1
60
74
100
V
V
A-B
Output Drive Frequency
f
EL
V
DD
= 3.0V, See Figure 1
300
370
430
Hz
Switching Frequency
f
SW
V
DD
= 3.0V, See Figure 1
50
70
90
kHz
Switching Duty Cycle
D
SW
V
DD
= 3.0V, See Figure 1
88
%
4
L
X
3
C
S
2
R
SW-OSC
1
V
DD
5
GND
6
V
B
7
V
A
8
R
EL-OSC
803_02.eps
IMP803
SO/ MicroSO
Part Number
Input Voltage
Regulated Output Voltage
Temperature Range
Pins-Package
IMP
803
LG
2.0V to 6.5V
Yes
40C to +85C
8-SO
IMP
803
IMA
2.0V to 6.5V
Yes
40C to +85C
8-MicroSO
IMP
803
SX*
2.0V to 6.5V
Yes
25C
Dice
IMP
803/
D1**
2.0V to 6.5V
Yes
25C
Dice
V
DD
, V
RSW-OSC
and V
REL-OSC
. . . . . . . . . . . . . . . 0.5V to +7.0V
V
CS
, L
X
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5V to +120V
Operating Temperature Range . . . . . . . . . . . . 40C to +85C
Storage Temperature Range . . . . . . . . . . . . . . 65C to +150C
Power Dissipation (SO) . . . . . . . . . . . . . . . . . . 400mW
Power Dissipation (MicroSO) . . . . . . . . . . . . . 300mW
V
A
, V
B
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5V to V
CS
(pin 3)
Unless otherwise noted, V
DD
= 3.0V, R
SW
= 750k
, R
EL
= 2.0M
, and T
A
= 25C.
Note: All voltages are referenced to GND.
These are stress ratings only and functional operation is not
implied. Exposure to absolute maximum ratings for prolonged
time periods may affect device reliability.
Pin Compatible With HV803 and IMP560
Ordering Information
Pin Configuration
Absolute Maximum Ratings
Electrical Characteristics
* Disable pad not active
** Disable pad active
Add /T to ordering part number for Tape and Reel.
I M P 8 0 3
I M P 8 0 3
2000 IMP, Inc.
Electroluminescent Lamp Driver
3
0
V
CS
(V), I
IN
(mA)
Inductor (
H)
803_03.eps
100
80
60
40
20
0
V
CS
, I
IN
vs. Inductor Value
200
600
800
400
1000
V
IN
= 3.0V
V
CS
I
IN
2.0
I
DD
(
A)
V
DD
(V)
800
700
600
500
400
300
I
DD
vs. V
DD
3.0
4.0
5.0
6.0
803_6.eps
L = 560
H
2.0
V
CS
(V), I
IN
(mA)
V
IN
(V)
100
80
60
40
20
0
V
CS
,
I
IN
vs. V
IN
3.0
4.0
5.0
6.0
L
= 330
H
V
CS
I
IN
803_07.eps
2.0
V
CS
(V), I
IN
(mA)
V
IN
(V)
100
80
60
40
20
0
V
CS
,
I
IN
vs. V
IN
3.0
4.0
5.0
6.0
L = 470
H
V
CS
I
IN
803_04.eps
2.0
V
CS
(V), I
IN
(mA)
V
IN
(V)
100
80
60
40
20
0
V
CS
,
I
IN
vs. V
IN
3.0
4.0
5.0
6.0
L
= 1mH
V
CS
I
IN
803_05.eps
2.0
V
CS
(V), I
IN
(mA)
V
IN
(V)
100
80
60
40
20
0
V
CS
,
I
IN
vs. V
IN
3.0
4.0
5.0
6.0
L
= 560
H
V
CS
In Regulation
I
IN
803_08.eps
Typical Characteristics
I M P 8 0 3
I M P 8 0 3
4
408-432-9100/www.impweb.com
2000 IMP, Inc.
Pin Descriptions
External Components
Pin Number
Name
Function
1
V
DD
Positive voltage supply for the IMP803. Inductor L may be connected here or to a
separate unregulated supply.
2
R
SW-OSC
Switch-mode resistor pin. Switching frequency is determined by an external resistor, R
SW
.
3
C
S
Boost converter storage capacitor. The voltage across the EL lamp is equal to twice the
voltage at C
S
.
4
L
X
Connection to flyback inductance, L.
5
GND
Ground pin.
6
V
B
EL lamp drive. The lamp is connected in a high-voltage bridge circuit with V
B
providing
the complementary connection to V
A
. The peak-to-peak AC voltage across the EL lamp is
thus two times V
CS
.
7
V
A
EL lamp drive. (See above)
8
R
EL-OSC
The EL lamp oscillator frequency setting pin. The oscillator frequency is controlled
by external resistor R
EL
.
External Component
Description and Selection Guide
Diode
Catch diode. A fast reverse recovery diode, with BV > 100, such as a 1N4148.
Capacitor C
S
This is the high voltage capacitor that stores the inductive energy transferred through the
catch diode. A 100 volt capacitor between 10nF and 100nF is recommended.
Resistor R
EL
The EL lamp oscillator frequency setting resistor. This resistor, connected between the
R
EL-OSC
pin and V
DD
, provides an oscillator frequency inversely proportional to R
EL
;
as R
EL
increases, the EL lamp frequency decreases along with the current drawn by the lamp.
Lamp color is also determined by this frequency. A 2M
resistor between the R
EL-OSC
pin and the
V
DD
supply results in a lamp frequency around 350Hz: a 1M
resistor will give 700Hz.
Resistor R
SW
Switching Oscillator frequency setting resistor. The switching oscillator resistor is connected
between the R
SW-OSC
pin and the V
DD
supply. The switching frequency is inversely proportional
to the resistor value, dropping as the resistance increases.
Inductor L
The inductor provides the voltage boost needed by means of inductive "flyback". The internal
MOSFET switch alternately opens and closes the ground connection for the inductor at the
L
X
pin. When this internal switch opens, the inductor potential will forward-bias the catch
diode and the current will pass through the storage capacitor C
S
, charging it to a high voltage.
Smaller inductors are preferred to prevent saturation. As the value of the inductor
increases (and the series DC resistance of the inductor decreases), the switching frequency
set by R
SW
should be increased to prevent saturation. In general, smaller value inductors that
can handle more current are more desirable when larger area EL lamps must be driven.
Lamp, R
CL
An external resistor (R
CL
) in series with the lamp will protect the output drivers from high transient
currents during lamp commutation.
The IMP803 generates high voltages and caution should
be exercised.
High Voltages Present
I M P 8 0 3
I M P 8 0 3
2000 IMP, Inc.
Electroluminescent Lamp Driver
5
+
V
DD
R
SW-OSC
C
S
L
X
R
EL-OSC
V
A
V
B
GND
8
7
6
5
1
2
3
4
IMP803
2k
2M
R
EL
750k
560
H
1
V
IN
= 3.0V
0.1
F
2
1N4148
L
10nF
Equivalent to
3 in
2
lamp
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5
)
2. Larger values may be required depending upon supply impedance.
R
CL
803_09.eps
ON = V
DD
OFF = 0V
0.1
F
100V
R
SW
C
S
Figure 1. 3.0V Application
Test and Application Circuit, 3.0V
Figure 1 shows the IMP803 configured to drive a 3-square-inch
EL lamp, represented as a 10nF capacitor. With a 3.0V input, the
EL lamp will be driven to moderate brightness.
+
V
DD
R
SW-OSC
C
S
L
X
R
EL-OSC
V
A
V
B
GND
8
7
6
5
1
2
3
4
IMP803
2k
2M
R
EL
750k
560
H
1
V
IN
= 5.0V
0.1
F
2
C
S
1N4148
6 in
2
lamp
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5
)
2. Larger values may be required depending upon supply impedance.
R
CL
803_10.eps
0.1
F
100V
ON = V
DD
OFF = 0V
R
SW
L
Figure 2. 5.0V Application
Test and Application Circuit, 5.0V
Figure 2 shows a 5.0V input application driving a 6-square-inch
EL lamp.
Application Information
PDF 
ZIP