HV833 (90286 байта)
HV833
HV833
Demo Kit
Available
High Voltage EL Lamp Driver
Features
General Description
❏ 1.8V to 6.5V operating supply voltage
The Supertex HV833 is a high voltage driver designed for driving
EL lamps of up to 35nF (10-12in2). The input supply voltage
range is from 1.8V to 6.5V. 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 ±90V.
The chip can be enabled/disabled by connecting the resistor on
RSW-OSC to VDD/ground.
❏ DC to AC conversion
❏ Separately adjustable lamp and converter frequency
❏ Output voltage regulation
❏ Enable/disable function
❏ Patented output timing for high efficiency
❏ <100nA shutdown current
The HV833 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 RSW-osc pin and the supply pin VDD. The EL lamp
driver frequency is set by an external resistor connected between
REL-osc pin and the VDD pin. An external inductor is connected
between the LX and VDD or VIN pins. A 0.003-0.1µF capacitor is
connected between CS and ground. The EL lamp is connected
between VA and VB.
❏ Split supply capability
❏ LCD backlighting
Applications
❏ Portable Transceivers
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 CS reaches a nominal value of
90V, 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 180V peak-to-peak
across the EL lamp.
❏ Remote Control Units
❏ Calculators
❏ PDAs
❏ Global Positioning Systems (GPS)
Typical Application
Enable Signal
ON=VDD
OFF=0
VDD
1 VDD
VA
8
2 RSW-osc
VB
7
3 REL-osc
CS 6
4 Gnd
LX 5
EL Lamp
+
VIN
_
1N914
HV833MG
LX
Cs
100V
09/05/02
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,
1 refer to the most current databook or to the Legal/Disclaimer page on the Supertex website.
HV833
Pin Configuration
Ordering Information
Package Options
Device
MSOP-8
Die
HV833
HV833MG*
HV833X
ςΑ
* Product supplied on 2500 piece carrier tape reels.
VDD
1
RSW-osc
2
REL-osc
3
Gnd
4
Absolute Maximum Ratings*
Supply Voltage, VDD
-0.5V to +7.5V
Output Voltage, VCs
-0.5V to +100V
Operating Temperature Range
MSOP-8
8
VA
7
VB
6
CS
5
LX
Top View
-25° to +85°C
Storage Temperature Range
-65°C to +150°C
MSOP-8 Power Dissipation
Enable/Disable Table
300mW
(See Typical Application on Front Page)
Note:
*All voltages are referenced to GND.
RSW resistor
HV833
VDD
Enable
0V
Disable
Electrical Characteristics
DC Characteristics (Over recommended operating conditions unless otherwise specified, TA=25°C)
Symbol
Parameter
Min
Typ
Max
Units
Conditions
4.0
Ω
I=100mA
RDS(on)
On-resistance of switching transistor
VCs
Max. output regulation voltage
80
90
100
V
VDD=1.8V to 6.5V
VA-B
Max. of differential output voltage
across lamp
160
180
200
V
VDD=1.8V to 6.5V
IDDQ
Quiescent VDD supply current
100
nA
RSW-osc = Low
IDD
Input current going into the VDD pin
150
µA
VDD=1.8V to 6.5V. See Figure 1.
IIN
Input current including inductor current
56
64
mA
VIN=3.3V. See Figure 1.
VCS
Output voltage on VCS
63
72
81
V
VIN=3.3V. See Figure 1.
fEL
VA-B output drive frequency
240
270
300
Hz
VIN=3.3V. See Figure 1.
fSW
Switching transistor frequency
55
65
75
KHz
VIN=3.3V. See Figure 1.
D
Switching transistor duty cycle
88
%
See figure 1.
Recommended Operating Conditions
Symbol
Parameter
Min
Typ
Max
Units
VDD
Supply voltage
1.8
6.5
V
fEL
VA-B output drive frequency
60
1000
Hz
TA
Operating temperature
-25
85
°C
Max
Units
Conditions
Enable/Disable Function Table
Symbol
Parameter
Min
Typ
Conditions
EN-L
Logic input low voltage
0
0.5
V
VDD=1.8V to 6.5V
EN-H
Logic input high voltage
VDD-0.5
VDD
V
VDD=1.8V to 6.5V
2
HV833
Block Diagram
LX
VDD
CS
RSW-OSC
Switch
Osc
Q
GND
C
_
Disable
VA
Vsen
+
Q
Vref
Output
Osc
Q
REL-OSC
VB
Q
Figure 1: Typical Application/Test Circuit
Enable Signal
ON=VDD
OFF=0
Equivalent to
10in2 lamp
VDD=VIN=3.3V
680Ω
VDD
1 VDD
VA
8
2 RSW-osc
VB
7
3 REL-osc
CS 6
4 Gnd
LX 5
29nF
1.0M
VIN
+
_
1.65M
4.7µF
HV833MG
1N914
LX*
220µH
0.01µF
100V
* Lx = 220µH Murata LQH43MN221K01
Typical Performance
Device
HV833MG
Lamp Size
10
in2
VIN
IIN
VCS
fEL
Brightness
TA
3.3V
56mA
72V
270Hz
5.0ft-lm
-25°C to +85°C
3
HV833
Typical Performance Curves for Figure 1 (EL Lamp= 10.0 in2, VIN=VDD).
Iin vs. Vin
60
80
50
Iin(mA)
70
60
50
40
1.0
2.0
3.0
4.0
5.0
6.0
40
30
20
1.0
7.0
2.0
3.0
4.0
Vin (V)
6.0
7.0
Iin vs. Vcs
Brightness vs. Vin
60
6
5
4
3
2
1
0
1.0
Iin (mA)
50
40
30
20
2.0
3.0
4.0
5.0
6.0
40
7.0
50
60
70
80
Vcs (V)
Vin (V)
Iin, Vcs, Brightness vs. Inductor Value
80
8
70
7
6
60
Vcs
Iin (mA), Vcs (V)
Brightness (ft-lm)
5.0
Vin (V)
50
5
40
4
Iin
30
3
2
20
Brightness
1
10
0
100
200
300
400
500
600
Inductor Value (µH)
4
700
800
900
0
1000
Brightness (ft-lm)
Vcs (V)
Vcs vs. Vin
90
90
HV833
Figure 2: Typical Application
Figure 2: VDD=3V, VIN=5.0V
Enable Signal
ON=VDD
OFF=0
VDD
1 VDD
VA
8
2 RSW-osc
VB
7
3 REL-osc
CS 6
4 Gnd
LX 5
EL Lamp
6in2
750K
VIN
+
_
1.0M
4.7µF
HV833MG
1N914
LX*
560µH
0.01µF
100V
* Lx = 560µH Murata LQH43MN561K01
Typical Performance
Device
HV833MG
Lamp Size
6.0
in2
VIN
IIN
VCS
fEL
Brightness
TA
5.0V
30mA
70V
440Hz
6.0ft-lm
-25°C to +85°C
5
HV833
Iin vs. Vin
Vcs vs. Vin
80
70
60
50
40
30
20
1.0
Iin(mA)
2.0
3.0
4.0
5.0
6.0
1.0
7.0
2.0
3.0
Vin (V)
5.0
6.0
7.0
60
70
80
Vin (V)
Iin vs. Vcs
Brightness vs. Vin
35
8
30
6
25
Iin (mA)
10
4
2
20
15
10
0
1.0
2.0
3.0
4.0
5.0
6.0
20
7.0
30
40
50
Vcs (V)
Vin (V)
Iin, Vcs, Brightness vs. Inductor Value
90
10
80
9
70
8
Vcs
60
Iin (mA), Vcs (V)
Brightness (ft-lm)
4.0
7
50
6
Brightness
40
5
30
4
Iin
20
3
10
2
0
100
200
300
400
500
600
Inductor Value (µH)
6
700
800
900
1
1000
Brightness (ft-lm)
Vcs (V)
Typical Performance Curves for Figure 2 (EL Lamp= 6.0 in2, VDD«=3.0V).
HV833
Figure 3: Typical Application
Figure 3: VDD = VIN = 3.0V
Enable Signal
ON=VDD
OFF=0
1 VDD
VA
8
EL Lamp
3in2
750K
2
+
VIN=VDD
_
RSW-osc
VB
7
3 REL-osc
CS 6
4 Gnd
LX 5
1.0M
4.7µF
1N914
LX*
560µH
HV833MG
0.01µF
100V
* Lx = 560µH Murata LQH43MN561K01
Typical Performance
Device
Lamp Size
VIN
IIN
VCS
fEL
Brightness
TA
HV833MG
3.0 in2
3.0V
20mA
60V
440Hz
4.0ft-lm
-25°C to +85°C
7
HV833
Typical Performance Curves for Figure 3 (EL Lamp= 3.0 in2, VIN=VDD).
Iin vs. Vin
25
Iin(mA)
2.0
3.0
4.0
5.0
6.0
20
15
10
5
1.0
7.0
2.0
3.0
Vin (V)
Brightness vs. Vin
25
8
20
Iin (mA)
10
6
4
2
5.0
6.0
7.0
70
80
90
Iin vs. Vcs
15
10
5
0
1.0
2.0
3.0
4.0
5.0
6.0
30
7.0
40
50
60
Vcs (V)
Vin (V)
Iin, Vcs, Brightness vs. Inductor Value
Iin (mA), Vcs (V)
Brightness (ft-lm)
4.0
Vin (V)
90
10
80
9
70
8
60
7
Vcs
50
6
40
5
Brightness
30
4
20
3
Iin
10
0
100
2
200
300
400
500
600
Inductor Value (µH)
8
700
800
900
1
1000
Brightness (ft-lm)
Vcs (V)
Vcs vs. Vin
90
80
70
60
50
40
30
1.0
HV833
External Component Description
External Component
Selection Guide Line
Diode
Fast reverse recovery diode, 100V 1N4148 or equivalent.
Cs Capacitor
0.003µF to 0.1µF, 100V capacitor to GND is used to store the energy transferred from the inductor.
REL-osc
The EL lamp frequency is controlled via an external REL resistor connected between REL-osc and VDD of the
device. The lamp frequency increases as REL decreases. As the EL lamp frequency increases, the amount
of current drawn from the battery will increase and the output voltage VCS will decrease. The color of the EL
lamp is dependent upon its frequency.
RSW-osc
The switching frequency of the converter is controlled via an external resistor, RSW between RSW-osc and VDD
of the device. The switching frequency increases as RSW decreases. With a given inductor, as the switching
frequency increases, the amount of current drawn from the battery will decrease and the output voltage, VCS,
will also decrease.
Lx Inductor
The inductor Lx is used to boost the low input voltage by inductive flyback. When the internal switch is on,
the inductor is being charged. When the internal switch is off, the charge stored in the inductor will be
transferred to the high voltage capacitor CS. The energy stored in the capacitor is connected to the internal
H-bridge and therefore to the EL lamp. In general, smaller value inductors, which can handle more current,
are more suitable to drive larger size lamps. As the inductor value decreases, the switching frequency of the
inductor (controlled by RSW) should be increased to avoid saturation.
220µH Murata (LQH43MN221) inductors with 5.4Ω series DC resistance is typically recommended. For
inductors with thesame inductance value but with lower series DC resistance, lower RSW value is needed to
prevent high current draw and inductor saturation.
Lamp
As the EL lamp size increases, more current will be drawn from the battery to maintain high voltage across
the EL lamp. The input power, (VIN x IIN), will also increase. If the input power is greater than the power
dissipation of the package (300mW), an external resistor in series with one side of the lamp is recommended
to help reduce the package power dissipation.
Enable/Disable Configuration
Split Supply Configuration for Battery
Voltages of Higher than 6.5V
The HV833 can be easily enabled and disabled via a logic control
signal on the RSW and REL resistors as shown in the Typical
Application Circuit on the front page. The control signal can be
from a microprocessor. RSW and REL are typically very high
values. Therefore, only 10’s of microamperes will be drawn from
the logic signal when it is at a logic high (enable) state. When
the microprocessor signal is high the device is enabled and when
the signal is low, it is disabled.
The Typical Application Circuit on the first page can also be used
with high battery voltages such as 12V as long as the input
voltage, VDD, to the HV833 device is within its specifications of
1.8V to 6.5V. Split supply configuration is shown on Figure 2.
09/05/02rev.8
©2002 Supertex Inc. All rights reserved. Unauthorized use or reproduction prohibited.
9
1235 Bordeaux Drive, Sunnyvale, CA 94089
TEL: (408) 744-0100 • FAX: (408) 222-4895
www.supertex.com
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