HV829A/B HV829A/B Advance Information High Voltage EL Lamp Driver Features General Description ❑ Processed with HVCMOS® technology The Supertex HV829A/B are high voltage EL lamp driver integrated circuits designed for driving EL lamps of up to 70nF at 1000Hz. The input supply voltage range is from 2.7V to 5.5V. These devices use a single inductor, a high voltage switching FET and a minimum number of passive components. The HV829A/B will supply the EL lamp with an AC square wave with a peak-to-peak voltage of two times the set regulated DC voltage. ❑ VDD voltage range = 2.7 to 5.5V DC ❑ Output load up to 70nF (20 in2 for 3.5nF/ in2 lamp) ❑ Adjustable DC-DC converter frequency ❑ Continious output voltage regulation control (from 50V to 200V) The HV829A/B has one internal oscillator and a high voltage EL lamp driver. The frequency for the external switching MOSFET is set by an external resistor connected between the RSW-osc pin and GND. The EL frequency for the HV829A is equal to the switching frequency divided by 64 where the EL frequency for the HV829B is equal to the switching frequency divided by 128. Gate of the external MOSFET is connected to the Gate pin. An external inductor is connected between the Drain of external MOSFET and VDD pin. A 0.01-2.5µF capacitor is connected between Cs and ground. The EL lamp is connected between VA and VB. The output voltage regulation level is controlled via the VREG pin for dimming and/or conservation of power. The output voltage regulation can be controlled continuously between 50V and 200V depending on the voltage applied to VREG pin (0.75V to 3V). Application ❑ Electronic Organizers ❑ Handheld Portable Computers ❑ Display Signs ❑ Portable Instrumentation Equipment 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 chosen by the user, 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 the AC voltage of +/- VREG voltage across the EL lamp. Typical Application Circuit Off=VDD On=GND VDD VA 8 2 RSW-osc VB 7 3 VREG Gate 6 4 GND CS 5 Lx BAV21 HV829ASG + VIN 1 VDD EL Lamp Vreg CIN CS 250V - VN2224N3 or TN2425N8 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, refer to the most current databook or to the Legal/Disclaimer page on the Supertex website. 1 HV829A/B Ordering Information Package Device Output EL Frequency SO-8 w/ Heat Slug Die HV829A Sw oscillator / 64 HV829ASG HV829AX HV829B Sw oscillator / 128 HV829BSG HV829AX ** Mounted on FR4 board, 25mm x 25mm x 1.57mm. Suggested Pin Configuration Absolute Maximum Ratings* Input Voltage to the external Inductor +18V VDD +7.0V Output voltage, VCS -.05V to +250V Operating Temperature -25°C to +85°C Storage Temperature -65°C to +150°C Power Dissipation VDD 1 8 VA RSW 2 7 VB VREG 3 6 Gate GND 4 5 CS 1.5W MSOP-8 Top View *Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is not implied. Continuous operation of the device at the absolute rating level may affect device reliability. All voltages are referenced to device ground. Electrical Characteristics DC Characteristics Symbol (Over recommended operating conditions unless otherwise specified, TA=25°C). Parameter VCS Max. output regulation voltage (VDD=2.7 to 5.5V, No load) fsw Inductor switching frequency Min Typ Max 42 50 58 90 100 110 135 150 165 180 200 220 20 25 30 Units VREG = 0.75V V Quiescent VDD supply current 400 nA Input current going into the VDD pin 400 µA IIN Input current including inductor current 195 mA IINQ Quiescent supply current (no load) 200 µA 100 µA VA– VB Differential output voltage across the lamp 100 116 200 220 270 300 330 380 400 440 VREG = 2.25V VREG = 3.0V IDDQ 84 VREG = 1.5V KHz IDD 180 Conditions VCS = 150V, CL = 57nF, RSW-OSC = 1M See Figure 1. VCS = 150V, RSW-OSC=1M VREG = 0.75V V VREG = 1.5V VREG = 2.25V VREG = 3.0V Recommended Operating Conditions fSW Inductor switching frequency 51.2 64 76.8 fEL Output drive frequency 0.8 1.0 1.2 tR Output rise time 235 300 365 tF Output fall time 235 300 365 tr-Gate Gate rise time 150 tf-Gate Gate fall time 50 2 KHz RSW-osc=400 , CL=70nF µs VCS=200V, RSW-osc=400 fEL=1KHz , CL=70nF, ns CG=2500pF Gate to GND , HV829A/B Enable/Disable Function Table VIN Inductor voltage 3.0 12 VDD device supply voltage 2.7 5.5 VGATE Internal supply voltage 10 Operating temperature -25 12 CL TA V 14 70 nF 85 °C * No LX or CS current when VDD=0V or Hi-Z Description Input Voltage (VDD) RSW-osc Outputs VA and VB Gate Output Disabled Hi VDD Hi-Z 0V Output Enabled Hi GND Oscillating Oscillating IC off 0V — Hi-Z 0V Functional Block Diagram Gate Cs VDD VREG Switch OSC VSENSE VA High Voltage Level Translators PWM Control HV829A HV829B Rsw-osc GND Switch OSC Divided by 64 Switch OSC Divided by 64 3 VB HV829A/B Figure 1: Typical Application/Test Circuit Off=VDD On=GND VDD 1MΩ Vreg=2.25V 1 VDD VA 8 2 RSW-osc VB 7 EL Lamp 3 VREG Gate 6 4 GND CS 5 Lx BAV21 HV829ASG + VIN 4.7µF VN2224N3 4.2µF 250V - Typical Performance Device HV829A/BSG Lamp Size 20 in2 VIN IDD VCS fSW fEL Brightness 9.0V 195mA 153V 25KHz 390Hz 18.5ft-lm * The inductor used is a 330µH J.W. Miller, max. DC resistance of 1.15Ω, part #PM105-331K. 09/05/02rev.2 ©2002 Supertex Inc. All rights reserved. Unauthorized use or reproduction prohibited. 4 1235 Bordeaux Drive, Sunnyvale, CA 94089 TEL: (408) 744-0100 • FAX: (408) 222-4895 www.supertex.com