HV825 High Voltage EL Lamp Driver IC Features ► ► ► ► ► ► ► General Description 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 The HV825 can be enabled/disabled by connecting the RSW-Osc resistor to VDD/GND. 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 RSW-Osc pin and the VDD supply pin. 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 0.01 to 0.1µF, 100V capacitor is connected between the CS pin and the GND pin. The EL lamp is connected between the VA pin and the VB pin. Applications ► ► ► ► ► 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. The typical output voltage that can be applied to the EL lamp is ±56V. Pagers Portable Transceiver Cellular phones Remote control units Calculators The switching BJT charges the external inductor and discharges it into the 0.01 to 0.1µF, 100V capacitor at the CS pin. The voltage at the CS pin will start to increase. The outputs VA and VB are configured as an H-bridge and are switching in opposite states to achieve a peak-to-peak voltage of two times the VCS voltage across the EL lamp. HV825 Block Diagram LX VDD CS RSW-Osc Switch Osc Q VA GND Q Output Osc Q VB REL-Osc Q HV825 Ordering Information Package Options Device HV825 8-Lead SO HV825LG 8-Lead MSOP HV825LG-G HV825MG HV825MG-G -G indicates package is RoHS compliant (‘Green’) Absolute Maximum Ratings Pin Configuration Parameter Value Supply voltage, VDD Operating Temperature Range Storage Temperature Range VDD 1 8 REL-Osc RSW-Osc 2 7 VA CS 3 6 VB LX 4 5 GND 0.5V to +2.5V -25°C to +85°C -65°C to +150°C MSOP-8 Power Dissipation 300mW SO-8 Power Dissipation 400mW HV825 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. (top view) Electrical Characteristics DC Characteristics (Over recommended operating conditions unless otherwise specified Symbol Parameter RDS(ON) - TA=25°C) Min Typ Max Units Conditions On-resistance of switching transistor - - 15 Ω IIN VDD supply current (including inductor current) - 30 38 mA VDD=1.5V. See test circuit IDDQ Quiescent VDD supply current - - 1.0 μA RSW-osc = GND VCS Output voltage on VCS 52 56 68 V VDD = 1.5V. See test circuit VA-B Differential output voltage across lamp 104 112 136 V VDD = 1.5V. See test circuit fEL VA-B output drive frequency 400 - - Hz VDD = 1.5V. See test circuit fSW Switching transistor frequency - 30 - KHz VDD = 1.5V. See test circuit D Switching transistor duty cycle - 88 - % --- 1.0 - 1.6 V --- 0 6.0 - nF --- -25 - +85 O C --- 0 - 0.2 V VDD = 1.0V-1.6V VDD-0.5 - VDD V VDD = 1.0V-1.6V I = 50mA Recommended Operating Conditions VDD Supply voltage CL Load Capacitance TA Operating temperature Enable/Disable Table VIL VIH Low level input voltage to RSW-osc resistor High level input voltage to RSW-osc resistor 2 HV825 Test Circuit ON = VDD OFF = GND Enable 1MΩ 1 VDD REL-Osc 2 RSW-Osc VA 7 3 CS VB 6 4 LX GND 5 8 750KΩ 560µH1 1N4148 VDD = VIN = 1.0V - 1.6V 0.1µF 0.01µF 100V 2.2KΩ CSW 1nF 4.7nF Equivalent to 1.5in2 lamp HV825LG or HV825MG Typical Performance Lamp Size VIN IDD VCS fEL Brightness 1.5in2 1.5V 30mA 56V 450Hz 3.65ft-lm Notes: 1. Murata part # LQH4N561K04 (DC resistance < 14.5Ω) External Component Description External Component Selection Guide Line Diode Fast reverse recovery, 1N4148 or equivalent. CS Capacitor 0.01 to 0.1µF, 100V capacitor to GND is used to store the energy transferred from the inductor. REL-Osc Resistor The lamp frequency is controlled via the REL-Osc. The lamp frequency increases as the REL-Osc decreases. As the lamp frequency increases, the amount of current drawn from the battery will increase and the output voltage VCS will decrease. This is because the lamp will draw more current from VCS when driven at higher frequencies. In general, as the lamp size increases, a larger REL-Osc is recommended to provide higher VCS. However, the color of the lamp is dependent upon its frequency and the shade of the color will change slightly with different frequencies. RSW-Osc Resistor The switching frequency of the inductor is controlled via the RSW-Osc. The switching frequency increases as the RSW-Osc decreases. 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 up the low input voltage. When the internal switch is on, the inductor is being charged. When the internal switch is off, the charge 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 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-Osc) should be increased to avoid saturation. The test circuit uses a Murata (LQH4N561) 560µH inductor. Using different inductor values or inductors from different manufacturers will affect the performance. As the inductor value decreases, smaller RSW-Osc values should be used. This will prevent inductor saturation. An inductor with the same inductance value, (560µH), but lower series resistance, will charge faster. The RSW-Osc resistor value needs to be decreased to prevent inductor saturation and high current consumption. CSW Capacitor A 1nF capacitor is recommended from RSW-Osc pin to GND. This capacitor is used to shunt any switching noise that may couple into the RSW-Osc pin. 3 HV825 8-Lead SOIC (Narrow Body) Package (LG) 4.90 ± 0.10 8 6.00 ± 0.20 Notes: 1. All dimensions in millimeters. Angles in degrees. 2. If the corner is not chamfered, then a Pin 1 identifier must be located within the area indicated. Note 2 3.90 ± 0.10 1 5° - 15° (4 PLCS) Top View 0.17 - 0.25 0.25 - 0.50 45° Note 2 1.25 MIN 1.75 MAX 0° - 8° 0.40 - 1.27 0.10 - 0.25 1.27BSC 0.31 - 0.51 End View Side View 4 HV825 8-Lead MSOP Package Outline (MG) 3x3mm body, 1.10mm height (max), 0.65mm pitch D θ1 (x4) 8 E E1 L2 Note 1 (Index Area D1/2 x E1/2) L 1 Top View View B A A Seating Plane θ L1 Gauge Plane View B A2 A Seating Plane b e A1 View A-A Side View Note 1: A Pin 1 identifier must be located in the index area indicated. The Pin 1 identifier may be either a mold, or an embedded metal or marked feature. Symbol Dimension (mm) MIN A 0.75 A1 0.00 A2 0.75 b 0.22 D 2.80 E 4.65 E1 e 2.80 NOM - - 0.85 - 3.00 4.90 3.00 MAX 1.10 0.15 0.95 0.38 3.20 5.15 3.20 L L1 L2 0.40 0.65 BSC 0.60 0.80 θ 0 0.95 REF 0.25 BSC O θ1 5O - - 8O 15O JEDEC Registration MO-187, Variation AA, Issue E, Dec. 2004. Drawings not to scale. (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to http://www.supertex.com/packaging.html.) Doc.# DSFP-HV825 A111306 5