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Details, datasheet, quote on part number:HV823LG
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Datasheet text preview:
HV823
HV823 High Voltage EL Lamp Driver
Ordering Information
Package Options Device HV823 Input Voltage 2.0V to 9.5V 8-Lead SO HV823LG Die HV823X
Features
Processed with HVCMOS® technology 2.0V to 9.5V operating supply voltage DC to AC conversion 180V peak-to-peak typical output voltage Large output load capability typically 50nF Permits the use of high-resistance elastomeric lamp components Adjustable output lamp frequency to control lamp color, lamp life, and power consumption Adjustable converter frequency to eliminate harmonics and optimize power consumption Enable/disable function Low current draw under no load condition
General Description
The Supertex HV823 is a high-voltage driver designed for driving EL lamps of up to 50nF. EL lamps greater than 50nF can be driven for applications not requiring high brightness. The input supply voltage range is from 2.0 to 9.5V. 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 by connecting the resistors on RSW-osc and REL-osc to VDD and disabled when connected to GND. The HV823 has two internal oscillators, a switching MOSFET, and a high-voltage EL lamp driver. The frequency for the switching converter 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 pins. A 0.01µF to 0.1µF capacitor is connected between CS and GND. The EL lamp is connected between VA and VB. The switching MOSFET charges the external inductor and discharges it into the Cs capacitor. 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 switched in opposite states to achieve 180V peak-to-peak across the EL lamp.
Applications
Handheld personal computers Electronic personal organizers GPS units Pagers Cellular phones Portable instrumentation
Pin Configuration
V DD RSW-osc Cs Lx
1 2 3 4
8 7 6 5
Absolute Maximum Ratings*
Supply Voltage, VDD Output Voltage, VCs Operating Temperature Range Storage Temperature Range Power Dissipation
Note: *All voltages are referenced to GND. 11/12/01
R EL-osc VA VB GND
-0.5V to +10V -0.5V to +120V -25°C to +85°C -65°C to +150°C 400mW
SO-8
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 1 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.
HV823
Electrical Characteristics
DC Characteristics (VIN = 3.0V, RSW = 750K, REL = 2.0M, TA = 25°C unless otherwise specified)
Symbol RDS(on) VCS VA - VB IDDQ IDD Parameter On-resistance of switching transistor Output voltage VCS Regulation Output peak to peak voltage Quiescent VDD supply current, disabled Input current going into the VDD pin 80 160 Min Typ 2 90 180 30 150 Max 6 100 200 100 200 300 500 IIN VCS fEL f SW D Input current including inductor current Output voltage on VCS VA-B output drive frequency Switching transistor frequency Switching transistor duty cycle 60 330 50 25 70 380 60 88 33 85 450 70 Units V V nA µA µA µA mA V Hz KHz % I = 100mA VIN = 2.0 to 9.5V VIN = 2.0V to 9.5V RSW-osc = Low VIN = 3.0V. See Figure 1. VIN = 5.0V. See Figure 2. VIN = 9.0V. See Figure 3. VIN = 3.0V. See Figure 1. VIN = 3.0V. See Figure 1. VIN = 3.0V. See Figure 1. VIN = 3.0V. See Figure 1. Conditions
Recommended Operating Conditions
Symbol VDD TA Supply voltage Operating temperature Parameter Min 2.0 -25 Typ Max 9.5 +85 Units V °C Conditions
Enable/Disable Table
RSW resistor VDD 0V
(See Figure 4)
HV823 Enable Disable
2
HV823
Block Diagram
Lx VDD Cs RSW-osc Enable * Switch Osc
Q
GND Disable
VA + C _
Q
Vref Output Osc
Q
VB REL-osc
Q
* Enable is available in die form only.
Figure 1: Test Circuit, VIN = 3.0V
ON = VDD OFF = 0V
(Low input current with moderate output brightness).
2M
1
750K 560µH VDD = VIN = 3.0V 1N4148 0.1µF
2 1
VDD
REL-osc VA VB GND
8
2.0K
2 3 4
RSW-osc Cs Lx
7
10nF
6 5
Equivalent to 3 square inch lamp.
0.1µF 100V
HV823
Typical Performance
Lamp Size 3.0
Notes: 1. Murata part # LQH4N561K04 (DC resistance < 14.5) 2. Larger values may be required depending upon supply impedance.
VIN 3.0v
IIN 25mA
VCS 65v
f EL 385Hz
Brightness 6.5ft-lm
in2
For additional information, see Application Notes AN-H33 and AN-H34.
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