IMP IMP803 High-voltage el lamp driver Datasheet

IMP803
POWER MANAGEMENT
Key Features
High-Voltage EL Lamp Driver
The IMP803 is an Electroluminescent (EL) lamp driver with the four EL
lamp driving functions on-chip. These are the switch-mode power supply, 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-topeak. 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.
◆ Low Power: 420µA typical VDD current
◆ Wide operating voltage range - from 2.0V to 6.5V
◆ 180V peak-to-peak typical AC output voltage
◆ Large output load capability - drive lamps
with more than 30nF capacitance
◆ Adjustable output lamp frequency for control of
lamp color, lamp life, and power consumption
◆ Adjustable converter frequency to minimize
power consumption
◆ Device can be Enabled/Disabled
◆ Low quiescent current – 20nA (disabled)
◆ High-Voltage CMOS Process
◆ MicroSO package option
Applications
The IMP803 is available in MicroSO and SO-8 packages and in die or
wafer form.
◆
◆
◆
◆
◆
◆
◆
Block Diagram
VDD
RSW-OSC
GND
GPS units/Pagers/Cellular phones
PDAs/Handheld computers
Safety illumination
Portable instrumentation
Battery-operated displays
LCD modules
Toys
4
1
2
3
Switch
Oscillator
LX
CS
5
Q
+
7
C
Regulation
Control
–
VREF
VA
Q
Bridge
Output
Driver
IMP803
Q
6
REL-OSC
8
Lamp Drive
Oscillator
VB
Q
803_01.eps
© 2000 IMP, Inc.
408-432-9100/www.impweb.com
1
IMP803
Pin Configuration
SO/ MicroSO
VDD
1
RSW-OSC
2
8
REL-OSC
7
CS
VA
3
6
VB
LX
4
5
GND
IMP803
Pin Compatible With HV803 and IMP560
803_02.eps
Ordering Information
Part Number
IMP803LG
IMP803IMA
IMP803SX*
IMP803/D1**
Input Voltage
Regulated Output Voltage
Temperature Range
Pins-Package
2.0V to 6.5V
2.0V to 6.5V
2.0V to 6.5V
2.0V to 6.5V
Yes
Yes
Yes
Yes
– 40°C to +85°C
– 40°C to +85°C
25°C
25°C
8-SO
8-MicroSO
Dice
Dice
* Disable pad not active
** Disable pad active
Add /T to ordering part number for Tape and Reel.
Absolute Maximum Ratings
VDD, VRSW-OSC and VREL-OSC . . . . . . . . . . . . . . . –0.5V to +7.0V
VCS, LX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5V to +120V
Operating Temperature Range . . . . . . . . . . . . –40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . . . –65°C to +150°C
Power Dissipation (SO) . . . . . . . . . . . . . . . . . . 400mW
Power Dissipation (MicroSO) . . . . . . . . . . . . . 300mW
VA, VB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5V to VCS (pin 3)
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.
Electrical Characteristics
Unless otherwise noted, VDD = 3.0V, RSW = 750kΩ, REL = 2.0MΩ, and TA = 25°C.
Parameter
ON-resistance of MOS Switch
Output Voltage Regulation
Output Voltage Peak-to-peak (in regulation)
Quiescent VDD Supply Current, Disabled
Input Current at VDD Pin
Input Current at VDD Pin
Input Current: IDD Plus Inductor Current
Output Voltage at VCS
VA-B Output Drive Frequency
Switching Frequency
Switching Duty Cycle
2
Symbol
RDS(ON)
VCS
VA-VB
IDDQ
IDD
IDD
IIN
VCS
fEL
fSW
DSW
Conditions
I = 100mA
VDD = 2.0 to 6.5V
VDD = 2.0 to 6.5V
VRSW-OSC < 100mV
VDD = 3.0V, See Figure 1
VDD = 5.0V, See Figure 2
VDD = 3.0V, See Figure 1
VDD = 3.0V, See Figure 1
VDD = 3.0V, See Figure 1
VDD = 3.0V, See Figure 1
VDD = 3.0V, See Figure 1
408-432-9100/www.impweb.com
Min
80
160
60
300
50
Typ
Max
Units
3.5
90
180
20
420
500
20
74
370
70
88
8
100
200
200
700
750
31
100
430
90
Ω
V
V
nA
µA
µA
mA
V
Hz
kHz
%
© 2000 IMP, Inc.
IMP803
Typical Characteristics
IDD vs. VDD
VCS, IIN vs. Inductor Value
800
100
VIN = 3.0V
L = 560µH
700
VCS
60
IDD (µA)
VCS (V), IIN (mA)
80
40
20
500
400
IIN
0
0
600
200
400
600
800
Inductor (µH)
300
1000
2.0
3.0
6.0
803_6.eps
VCS, IIN vs. VIN
VCS, IIN vs. VIN
100
L = 330µH
L = 470µH
80
80
VCS (V), IIN (mA)
VCS
60
40
VCS
60
40
20
20
IIN
IIN
0
0
2.0
3.0
4.0
5.0
2.0
6.0
VIN (V)
3.0
4.0
5.0
VIN (V)
803_04.eps
VCS, IIN vs. VIN
6.0
803_07.eps
VCS, IIN vs. VIN
100
100
L = 1mH
L = 560µH
80
80
VCS
VCS (V), IIN (mA)
VCS (V), IIN (mA)
5.0
VDD (V)
803_03.eps
100
VCS (V), IIN (mA)
4.0
60
40
20
VCS
60
In Regulation
40
20
IIN
IIN
0
2.0
3.0
4.0
VIN (V)
© 2000 IMP, Inc.
5.0
6.0
803_05.eps
0
2.0
3.0
4.0
5.0
VIN (V)
Electroluminescent Lamp Driver
6.0
803_08.eps
3
IMP803
Pin Descriptions
Pin Number
Name
Function
1
VDD
2
RSW-OSC
Switch-mode resistor pin. Switching frequency is determined by an external resistor, RSW.
3
CS
Boost converter storage capacitor. The voltage across the EL lamp is equal to twice the
voltage at CS.
4
LX
Connection to flyback inductance, L.
5
GND
6
VB
EL lamp drive. The lamp is connected in a high-voltage bridge circuit with VB providing
the complementary connection to VA. The peak-to-peak AC voltage across the EL lamp is
thus two times VCS.
7
VA
EL lamp drive. (See above)
8
REL-OSC
Positive voltage supply for the IMP803. Inductor L may be connected here or to a
separate unregulated supply.
Ground pin.
The EL lamp oscillator frequency setting pin. The oscillator frequency is controlled
by external resistor REL.
External Components
External Component
Diode
Description and Selection Guide
Catch diode. A fast reverse recovery diode, with BV > 100, such as a 1N4148.
Capacitor CS
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
REL-OSC pin and VDD, provides an oscillator frequency inversely proportional to REL;
as REL increases, the EL lamp frequency decreases along with the current drawn by the lamp.
Lamp color is also determined by this frequency. A 2MΩ resistor between the REL-OSC pin and the
VDD supply results in a lamp frequency around 350Hz: a 1MΩ resistor will give ≈700Hz.
Resistor RSW
Switching Oscillator frequency setting resistor. The switching oscillator resistor is connected
between the RSW-OSC pin and the VDD 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
LX pin. When this internal switch opens, the inductor potential will forward-bias the catch
diode and the current will pass through the storage capacitor CS, 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 RSW 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, RCL
An external resistor (RCL) in series with the lamp will protect the output drivers from high transient
currents during lamp commutation.
High Voltages Present
The IMP803 generates high voltages and caution should
be exercised.
4
408-432-9100/www.impweb.com
© 2000 IMP, Inc.
IMP803
Application Information
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.
ON = VDD
2MΩ
OFF = 0V
REL
REL-OSC
8
2 RSW-OSC
VA
7
3 CS
VB
6
4 LX
GND
5
1 VDD
560µH1
L
RSW
RCL
1N4148
+
VIN = 3.0V
2kΩ
750kΩ
10nF
Equivalent to
3 in2 lamp
–
0.1µF2
CS
IMP803
0.1µF
100V
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5 Ω)
2. Larger values may be required depending upon supply impedance.
803_09.eps
Figure 1. 3.0V Application
Test and Application Circuit, 5.0V
Figure 2 shows a 5.0V input application driving a 6-square-inch
EL lamp.
ON = VDD
2MΩ
OFF = 0V
REL
1 VDD
560µH1
L
RSW
8
VA
7
2kΩ
2 RSW-OSC
RCL
3 CS
VB
6
4 LX
GND
5
6 in2 lamp
1N4148
+
VIN = 5.0V
REL-OSC
750kΩ
–
0.1µF2
CS
0.1µF
100V
IMP803
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5 Ω)
2. Larger values may be required depending upon supply impedance.
803_10.eps
Figure 2. 5.0V Application
© 2000 IMP, Inc.
Electroluminescent Lamp Driver
5
IMP803
Test and Application Circut, 6.0V
At higher input voltage levels, the IMP803 will drive large EL
lamps. Figure 3 shows a 6.0V circuit configuration that will drive
a 10 square-inch lamp.
2MΩ
REL
REL-OSC
8
2 RSW-OSC
VA
7
3 CS
VB
6
4 LX
GND
5
1 VDD
330kΩ
560µH1
L
RSW
RCL
10 in2 lamp
1N4148
+
VIN = 6.0V
2kΩ
–
0.1µF2
CS
IMP803
0.1µF
100V
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5 Ω)
2. Larger values may be required depending upon supply impedance.
803_11.eps
Figure 3. 6.0V Application
Enable/Disable Operation
Figure 4 shows that the IMP803 can be enabled via a logic gate that
connects RSW to VDD, and disabled by connecting it to ground.
Enable/Disable Table
RSW Connection
VDD
GND
CMOS
Gate
ON = VDD
IMP803 State
Enabled
Disabled
REL
OFF = 0V
1 VDD
REL-OSC
8
2 RSW-OSC
VA
7
3 CS
VB
6
4 LX
GND
5
RCL
RSW
L1
EL lamp
1N4148
+
VIN
–
0.1µF2
CS
0.1µF
100V
IMP803
Note:
1. Murata part # LQH4N561K04 (DC resistance <14.5 Ω)
2. Larger values may be required depending upon supply impedance.
803_12.eps
Figure 4. Enable/Disable Operation
6
408-432-9100/www.impweb.com
© 2000 IMP, Inc.
IMP803
Dual Supply Operation with 1.5V Battery
The IMP803 can also be operate from a single battery cell when a
regulated voltage higher than 2.0V is also available. This dual
supply configuration, shown in Figure 5, uses the regulated
voltage to operate the IMP803 while the energy for the highvoltage boost circuit comes from the battery.
The circuit of Figure 5 thus allows operation with batteries that are
below the 2V minimum specification or above the 6.0V maximum
operating voltage.
Regulated Voltage
(2.0V to 6.5V)
ON = VDD
REL
OFF = 0V
REL-OSC
8
2 RSW-OSC
VA
7
3 CS
VB
6
4 LX
GND
5
1 VDD
RSW
L
RCL
EL lamp
Battery
Voltage
1N4148
+
–
VIN
0.1µF*
CS
0.1µF
100V
IMP803
* Larger values may be required
depending upon supply impedance
803_13.eps
Figure 5. Dual Supply Operation
30
The IMP803 inductor switch resistance is typically below 3.5Ω, as
shown in Figure 6.
25
On Resistance (Ω)
Switch Resistance
20
15
10
5
0
1
2
3
4
5
VDD (V)
6
7
525_14.eps
Figure 6. Boost Switch On Resistance
© 2000 IMP, Inc.
Electroluminescent Lamp Driver
7
IMP803
Package Dimensions
SO (8-Pin)
Inches
Min
0°– 8°
Max
H
C
D
A
e
B
A1
SO (8-Pin).eps
a
+
E1 E
L
D
C
D
A
e
b
0.10mm
0.004in
Max
A
A1
B
C
e
E
H
L
D
0.053
0.004
0.013
0.007
0.069
0.010
0.020
0.010
1.35
0.10
0.33
0.19
1.75
0.25
0.51
0.25
0.157
0.244
0.050
0.197
3.80
5.80
0.40
4.80
0.050
0.150
0.228
0.016
0.189
1.27
4.00
6.20
1.27
2.00
MicroSO (8-Pin)**
MicroSO (8-Pin)
A2
Min
SO (8-Pin)*
L
E
Millimeters
MicroSO (8-Pin).eps
A1
IMP, Inc.
Corporate Headquarters
2830 N. First Street
San Jose, CA 95134-2071
Tel: 408-432-9100
Fax: 408-434-0335
e-mail: [email protected]
http://www.impweb.com
The IMP logo is a registered trademark of IMP, Inc.
All other company and product names are trademarks of their respective owners.
A
–––––
0.0433
A1
0.0020
0.0059
A2
0.0295
0.0374
b
0.0098
0.0157
C
0.0051
0.0091
D
0.1142
0.1220
e
0.0256 BSC
E
0.193 BSC
E1
0.1142
0.1220
L
0.0157
0.0276
a
0°
6°
* JEDEC Drawing MS-012AA
** JEDEC Drawing MO-187AA
––––
1.10
0.050
0.15
0.75
0.95
0.25
0.40
0.13
0.23
2.90
3.10
0.65 BSC
4.90 BSC
2.90
3.10
0.40
0.70
0°
6°
803_t01.at3
© 2000 IMP, Inc.
Printed in USA
Publication #: 2006
Revision:
B
Issue Date:
07/11/00
Type:
Product