Page 1
High Voltage EL Lamp Driver
Ordering Information
Package Options
Device MSOP-8 SO-8 Die
HV826 HV826MG* HV826LG HV826X
* Product supplied on 2500 piece carrier tape reels.
HV826
Features
❏ 1.8V to 3.5V operating supply voltage
❏ DC to AC conversion
❏ Adjustable output frequency
❏ Adjustable switch frequency
❏ Output voltage regulation
❏ Enable/disable function
Applications
❏ Mobile cellular phones
❏ Pagers
❏ Portable Transceivers
❏ Remote Control Units
❏ Calculators
General Description
The Supertex HV826 is a high voltage driver designed for driving
EL lamps. The input supply voltage range is from 1.8V to 3.5V.
The device uses a single inductor and a minimum number of
passive components. The nominal regulated output voltage that
is applied to the EL lamp is ±80V. The chip can be enabled/
disabled by connecting the resistor on R
The HV826 has two internal oscillators, a switching MOSFET,
and a high voltage EL lamp driver. The frequency for the
switching MOSFET is set by an external resistor connected
between the R
pin and the supply pin VDD. The EL lamp
SW-osc
driver frequency is set by an external resistor connected between R
connected between the L
is connected between C
between V
pin and the VDD pin. An external inductor is
EL-osc
and VB.
A
and VDD pins. A 0.01-0.1µF capacitor
X
and ground. The EL lamp is connected
S
The switching MOSFET charges the external inductor and
discharges it into the capacitor at CS. The voltage at CS will start
to increase. Once the voltage at C
reaches a nominal value of
S
80V, the switching MOSFET is turned OFF to conserve power.
The outputs VA and VB are configured as an H bridge and are
switching in opposite states to achieve 160V peak-to-peak
across the EL lamp.
to VDD/ground.
SW-OSC
Absolute Maximum Ratings*
Supply Voltage, V
Output Voltage, V
DD
Cs
Operating Temperature Range -25° to +85°C
Storage Temperature Range -65°C to +150°C
MSOP-8 Power Dissipation 250mW
SO-8 Power Dissipation 400mW
Note:
*All voltages are referenced to GND.
11/12/01
Supertex Inc. does not recommend the use of its products in life support applications and will not knowingly sell its products for use in such applications unless it receives an adequate "products liability
indemnification insurance agreement." Supertex does not assume responsibility for use of devices described and limits its liability to the replacement of devices determined to be defective due to
workmanship. No responsibility is assumed for possible omissions or inaccuracies. Circuitry and specifications are subject to change without notice. For the latest product specifications, refer to the
Supertex website: http://www.supertex.com. For complete liability information on all Supertex products, refer to the most current databook or to the Legal/Disclaimer page on the Supertex website.
-0.5V to +4.5V
-0.5V to +100V
Pin Configuration
ςΑ
1
V
DD
R
SW-osc
R
EL-osc
Gnd L
1
2
3
4
MSOP-8
and
SO-8
Top View
V
8
A
7
V
B
C
6
S
5
X
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Electrical Characteristics
DC Characteristics (Over recommended operating conditions unless otherwise specified, T
Symbol Parameter Min Typ Max Units Conditions
R
DS(on)
V
Cs
V
A-B
I
DDQ
I
DD
I
IN
V
CS
f
EL
f
SW
D Switching transistor duty cycle 88 % See figure 1.
On-resistance of switching transistor 7.0 Ω I=100mA
Max. output regulation voltage 75 80 85 V VDD=1.8V to 3.5V
Max. of differential output voltage
across lamp
150 160 170 V V
Quiescent VDD supply current 100 nA R
Input current going into the VDD pin 150 µAVDD=1.8V to 3.5V. See Figure 1.
Input current including inductor current 35 45 mA VIN=1.5V. See Figure 1.
Output voltage on V
V
output drive frequency 300 375 450 Hz VIN=1.5V. See Figure 1.
A-B
CS
65 70 V VIN=1.5V. See Figure 1.
Switching transistor frequency 80 KHz VIN=1.5V. See Figure 1.
=25°C)
A
=1.8V to 3.5V
DD
= Low
SW-osc
Recommended Operating Conditions
Symbol Parameter Min Typ Max Units Conditions
V
DD
f
EL
T
A
Supply voltage 1.8 3.5 V
V
output drive frequency 60 1000 KHz
A-B
Operating temperature -25 85 °C
HV826
Enable/Disable Function Table
Symbol Parameter Min Typ Max Units Conditions
EN-L Logic input low voltage 0 0.5 V V
EN-H Logic input high voltage V
-0.5 V
DD
DD
VVDD=1.8V to 3.5V
=1.8V to 3.5V
DD
2
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Block Diagram
V
DD
R
SW
GND
Rel
Switch
Osc
Disable
HV826
L
X
C
S
Q
V
+
C
_
Vref
Vsen
Q
A
Output
Osc
Q
V
B
Q
Figure 1: Typical Application
ON=V
DD
OFF=0
V
+
V
IN
_
4.7uF
* LX = Murata LQH4N221K04
Enable Signal
DD
560K
1.0M
V
DD
V
1
DD
R
2
SW-osc
R
3
EL-osc
Gnd L
4
HV826MG or
HV826LG
=3V
8
V
A
V
7
B
C
6
S
5
X
Operating V
1N4148
*
L
X
220uH
0.1µF
100V
voltage: 1.8V to 3.5V
DD
EL lamp size: Up to 2.5 in
Brightness: 3.0 to 5.0ft-lm
EL Lamp
2
Typical Performance
Device Lamp Size V
HV826MG 1.6 in
2
IN
I
IN
V
CS
f
Brightness T
EL
A
1.5V 35mA 66V 345Hz 5.0ft-lm -25°C to +85°C
3
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Typical Performance Curves for Figure 1 (1.6 in.2 lamp)
HV826
VCS vs. V
100
80
60
(V)
40
CS
20
V
0
1234
B
rightness
8
6
(ft-lm)
4
2
0
Brightness
1234
IN
V
vs. V
V
IN
(V)
IN
(V)
IN
IIN vs. V
40
30
20
(mA)
10
IN
I
0
1234
IN
V
IN
(V)
IIN vs. VCS
40
30
20
(mA)
IN
I
10
0
60 70 80 90
V
CS (V)
90
80
70
(V)
60
CS
50
40
(mA), V
30
IN
I
20
10
0
IIN, VCS, B
rightness vs. Inductor Value
Vdd = 3.0V Vin = 1.5V
V
= 3.0V V
DD
= 1.5V
IN
100 220 330 560 900
I
nductor Value
(µH)
6.0
5.0
4.0
3.0
2.0
1.0
0.0
(ft-lm)
Brightness
4
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Figure 2: Typical Application
HV826
ON=V
DD
OFF=0
+
VIN=V
DD
_
4.7uF
* LX = Murata LQH4N561K04
Typical Performance
Device Lamp Size V
HV826MG 3.0 in
2
Figure 2: V
Enable Signal
=3.0V=V
IN
DD
Equivalent to 3 inch2 lamp
2.0K
V
1
DD
8
V
A
750K
2.0M
R
2
SW-osc
R
3
EL-osc
Gnd L
4
HV826MG/LG
V
7
B
C
6
S
1N4148
5
X
LX*
560uH
0.01µF
100V
Operating V
voltage: 1.8V to 3.5V
DD
EL lamp size: Up to 4.5 in
Brightness: 3.0 to 5.0ft-lm
DD
I
DD
V
CS
f
Brightness T
EL
A
3.0V 23mA 80V 195Hz 4.0ft-lm -25°C to +85°C
10nF
2
5
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)
Typical Performance Curves for Figure 2 (3.0 in.2 lamp)
HV826
VCS vs. V
IN
100
80
60
(V)
40
CS
V
20
0
1234
IN
(V)
V
B
rightness
vs. V
IN
5
4
(ft-lm)
3
2
1
0
Brightness
1234
IN
(V)
V
IIN vs. V
IN
25
20
15
(mA)
10
IN
I
5
0
1234
IN
(V)
V
IIN vs. VCS
25
20
15
10
(mA)
IN
I
5
0
50 60 70 80 90
CS (V)
V
90
80
70
(V)
60
CS
50
40
(mA), V
30
IN
I
20
10
0
IIN, VCS, B
IIN (mA)
rightness vs. Inductor Value
Brightness (ft-lm)
VCS (V
100 330 470 560 900
nductor Value
I
(µH)
5.0
4.0
3.0
2.0
1.0
0.0
(ft-lm)
Brightness
©2001 Supertex Inc. All rights reserved. Unauthorized use or reproduction prohibited.
11/12/01
1235 Bordeaux Drive, Sunnyvale, CA 94089
TEL: (408) 744-0100 • FAX: (408) 222-4895
6
www.supertex.com
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