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HV825
Absolute Maximum Ratings*
Supply voltage, V
DD
-0.5V to +2.5V
Operating Temperature Range
-25
°
C to +85
°
C
Storage Temperature Range
-65
°
C to +150
°
C
MSOP-8 Power Dissipation
300mW
SO-8 Power Dissipation
400mW
Note
:
*All voltages are referenced to GND.
High Voltage EL Lamp Driver
Features
Processed with HVCMOS
technology
1.0V to 1.6V operating supply voltage
DC to AC conversion
Output load of typically up to 6nF
Adjustable output lamp frequency
Adjustable converter frequency
Enable function
General Description
The Supertex HV825 is a high voltage driver designed for driving
EL lamps typically up to 6nF. The input supply voltage range is
from 1.0V to 1.6V. The device uses a single inductor and a
minimum number of passive components. Typical output
voltage that can be applied to the EL lamp is
±
56V.
The HV825 can be enabled/disabled by connecting the R
SW-osc
resistor to V
DD
/ground.
The HV825 has two internal oscillators, a switching bipolar
junction transistor (BJT), and a high voltage EL lamp driver. The
frequency for the switching BJT is set by an external resistor
connected between the R
SW-osc
pin and the supply pin V
DD
. The
EL lamp driver frequency is set by an external resistor connected
between R
EL-osc
pin and the V
DD
pin. An external inductor is
connected between the L
X
and V
DD
pins. A 0.01 to 0.1
μ
F, 100V
capacitor is connected between C
S
and ground. The EL lamp is
connected between V
A
and V
B
.
The switching BJT charges the external inductor and discharges
it into the 0.01 to 0.1
μ
F, 100V capacitor at C
S
. The voltage at C
S
will start to increase. The outputs V
A
and V
B
are configured as
an H-bridge and are switching in opposite states to achieve a
peak-to-peak voltage of two times the V
CS
voltage across the EL
lamp.
Pin Configuration
Applications
Pagers
Portable Transceiver
Cellular phones
Remote control units
Calculators
1
2
3
4
8
7
6
5
V
DD
R
EL-osc
V
A
V
B
GND
R
SW-osc
C
s
L
x
top view
SO-8/MSOP-8
For detailed circuit and application information, please refer
to application notes AN-H33 and AN-H34.
Package Options
Device
Input Voltage
8-Lead SO
MSOP-8
Die
HV825
1.0 to 1.6V
HV825LG
HV825MG*
HV825X
* Product supplied on 2500 piece carrier tape reels.
Ordering Information
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.