Supertex inc. HV86 Features Adjustable output regulation for dimming Lamp fade-in/fade-out capability Low audible noise 80V PP output voltage for higher brightness.v enable input logic high Single cell lithium ion compatible One miniature inductor to power both lamps Separately adjustable lamp and converter frequencies Split supply capability 6-Lead QFN package Applications Dimmable, Low Noise, Dual EL Lamp Driver Dual display cellular phones Keypad and LCD backlighting PDAs Handheld wireless communication products Global Positioning Systems (GPS) General Description The Supertex HV86 is a low noise, dimmable, high voltage, dual EL Lamp driver designed for driving two electroluminescent (EL) Lamps with a combined area of.0 square inches. The input supply voltage range is from.v to.v. Enable input logic high can go as low as.v, which allows logic interface operating from typical.8v supplies. The device is designed to minimize audible noise emitted by the EL Lamps. The device uses a single inductor and a minimum number of passive components. Using the internal reference voltage, Typical Application Circuit the regulated output voltage is at a nominal value of 0V. The EL Lamps will therefore see ±0V. The two EL Lamps can be turned ON and OFF using two CMOS logic inputs, and EN. The driver is disabled when both and EN are at logic low. The HV86 has two internal oscillators, a switching MOSFET, and two high voltage EL Lamp driver H-bridges. Each driver has its own half bridge common output, and COM, which significantly minimizes the DC offset seen by the EL Lamp. The frequency for the switching MOSFET is set by an external resistor connected between the pin and the supply pin. The EL Lamp driver frequency is set by an external resistor connected between the pin and the pin. An external inductor is connected between the LX and pins or VIN for split supply applications. Depending upon the EL Lamp sizes, a.0nf to 0.0nF capacitor is connected between the CS and ground. As 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 0V, the switching MOSFET is turned OFF to conserve power. EL Lamp dimming can be accomplished by applying a PWM logic signal to the PWM pin. The EL Lamp brightness will be inversely proportional to the PWM duty cycle. The HV86 can also slowly turn the EL Lamp ON/OFF giving a fade ON/ OFF appearance. V IN =. to.v.7µf =.0V 0.µF ON =. to OFF = 0 to 0.V 00µH Coilcraft LPS0.MΩ N8 7 8 VREG VOUT LX CS.0MΩ HV86K7-G 8kΩ 0 COM EN VREF PWM GND.µF 6 6.nF 00V NPO
Ordering Information Device HV86 -G indicates package is RoHS compliant ( Green ) 6-Lead QFN.00x.00mm body 0.80mm height (max) 0.0mm pitch HV86K7-G Pin Configuration VREF VREG VOUT PWM 6 0 COM 6 7 8 Absolute Maximum Ratings Parameter Value, supply voltage -0.V to.v Operating temperature Storage temperature -0 C to +8 C -6 C to +0 C Power dissipation.6w, output voltage -0.V to +0V 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. Note: Pads are at the bottom of the package. Center heat slug is at ground potential. Product Marking H86 YWLL EN GND LX CS 6-Lead QFN Package Y = Last Digit of Year Sealed W = Code for Week Sealed L = Lot Number = Green Packaging Package may or may not include the following marks: Si or 6-Lead QFN Package Thermal Resistance Package 6-Lead QFN θ ja 60 C/W Recommended Operating Conditions Sym Parameter Min Typ Max Units Conditions Supply voltage. -. V --- f SW Switching frequency 0-00 khz --- EL output frequency 00-00 Hz --- C LOAD Total EL Lamp capacitance load 0-0 nf --- T A Operating temperature -0 - +8 C --- Electrical Characteristics (Over recommended operating conditions unless otherwise specified) Sym Parameter Min Typ Max Units Conditions R DS(ON) On-resistance of switching transistor - - 7.0 Ω I = 00mA Maximum output regulation voltage 80 0 00 V - 78 -, V REG =.0V Output regulation voltage - 6 - V, V REG = 0.86V - -, V REG = 0.6V V REG External input voltage range 0 -.0 V
Electrical Characteristics (cont.) Sym Parameter Min Typ Max Units Conditions V REFH V REF output high voltage..6.0 V I REF(SOURCE) Average sourcing current from V REF pin - 6.0 - µa I REF(SINK) Average sinking current from V REF pin - 6.0 - µa I DDQ Quiescent supply current - - 00 - - 00 - - 00 I DD Input current going into the pin - - 0 µa na =.V, = EN = PWM = low =.0V, = EN = PWM = low =.V, = EN = PWM = low, R EL =.0MΩ, R SW = 8kΩ I IN Input current including inductor current - 0 ma V IN =.V (see Test Circuit) EL Lamp frequency 60 0 0 Hz R EL =.0MΩ f SW Switching transistor frequency 8 00 6 khz R SW = 8kΩ PWM Input PWM frequency 0-00 khz --- D Switching transistor duty cycle - 88 - % --- V IH Enable PWM input logic high voltage. - V V IL Enable PWM input logic low voltage 0-0. V I IH Enable PWM input logic high current - -.0 µa V IH = I IL Enable PWM input logic low current - - -.0 µa V IL = 0V, C IN Enable PWM input capacitance - - pf --- Function Table EN COM IC 0 0 Hi Z Hi Z Hi Z Hi Z OFF 0 Hi Z ON Hi Z ON ON 0 ON Hi Z ON Hi Z ON ON ON ON ON ON Typical Performance ( lamp size = lamp size =.6in ) (V) V IN (V) Lamp I IN (ma) ON 6. (V PEAK ) (Hz) Lamp Brightness (cd/m).0 -.0.0 ON 6. 88 -.0 and ON.8.0.0
Figure : Block Diagram LX CS Enable EN Enable PWM Switch Oscillator 0 to 88% C + - V SENSE Output Drivers VREG 60pF.6V V REF VOUT GND x EL Freq. x EL Freq. COM PWM VREF Figure : Test Circuit I IN V IN.7µF 00µH Coilcraft LPS0 N8.MΩ I DD 0.µF ON =.V to OFF = 0V to 0.V.0MΩ 8kΩ EN VREF VREG VOUT LX CS PWM 7 HV86K7 GND 8 COM 0.nF 00V NPO 60Ω 60Ω nf nf.µf 6 6
Figure : Typical Waveform, and Differential Waveform - Split Supply Configuration The HV86 can also be used for handheld devices operating from a battery where a regulated voltage is available. This is shown in Figure. The regulated voltage can be used to run the internal logic of the HV86. The amount of current necessary to run the internal logic is 0µA max. Therefore, the regulated voltage could easily provide the current without being loaded down. Enable/Disable Configuration and outputs can be enabled and disabled via a logic control signal on the and EN pins respectively. When is high/low, the Lamp () will be ON/OFF. When EN is high/low, the Lamp () will be ON/OFF. The control signal can be from a microprocessor. Figure : Split Supply and Enable/Disable Configuration Battery Voltage = V IN + _ C IN L X R REG D Regulated Voltage = + _ C DD R EL R SW 7 8 VREG VOUT LX CS EN VREF PWM 6 C REF HV86 GND 6 COM 0 C S
Pin Configuration and External Component Description Pin # Name Description External resistor from to sets the EL frequency. The EL frequency is inversely proportional to the external R EL resistor value. Reducing the resistor value by a factor of two will result in increasing the EL frequency by two. = (.0MΩ 0Hz) / R EL External resistor from to sets the switch converter frequency. The switch converter frequency is inversely proportional to the external R SW resistor value. Reducing the resistor value by a factor of two will result in increasing the switch converter frequency by two. f SW = (8kΩ 00kHz) / R SW Low voltage input supply pin. Enable input signal for EL Lamp. CMOS logic input pin. Refer to the function table. EN Enable input signal for EL Lamp. CMOS logic input pin. Refer to the function table. 6 GND Device ground. 7 LX 8 CS Drain of internal switching MOSFET. Connection for an external 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 C S. 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 R SW ) should be increased to avoid saturation. Connect a 00V capacitor between this pin and ground. This capacitor stores the energy transferred from the inductor. EL Lamp connection. 0 COM Common connection for Lamp. Common connection for Lamp. EL Lamp connection. PWM PWM pulse input for EL Lamp dimming. The duty cycle of the PWM signal is inversely proportional to the output voltage. If PWM dimming is not desired, then the PWM pin should be tied to ground. VOUT Switched internal reference voltage. VREG 6 VREF Input voltage to set regulation voltage. This pin allows an external voltage source to control the amplitude. EL Lamp dimming can be accomplished by varying the input voltage to VREG. The voltage is approximately 7 times the voltage seen on VREG. External resistor connected between VREG and VOUT pins controls the charging rate. The charging rate is inversely proportional to the resistor value. Internal reference voltage to set the regulation voltage. Connect an external capacitor (C REF ) from VREF to ground to slowly brighten the lamp during power-up and dim down the lamp during powerdown. The size of the capacitor determines the time taken to brighten up or dim down. If fade-in and fade-out are not required, this pin should be left floating. Fade in/fade out time = C REF x 0 x 0 sec. 6
6-Lead QFN Package Outline (K7).00x.00mm body, 0.80mm height (max), 0.0mm pitch 6 D D 6 Note (Index Area D/ x E/) Note (Index Area D/ x E/) e E E b Top View Bottom View View B Note θ L A A Side View A Seating Plane L Note View B Notes:... A Pin identifier must be located in the index area indicated. The Pin identifier can be: a molded mark/identifier; an embedded metal marker; or a printed indicator. Depending on the method of manufacturing, a maximum of 0.mm pullback (L) may be present. The inner tip of the lead may be either rounded or square. Dimension (mm) Symbol A A A b D D E E e L L θ (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.) Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such applications unless it receives an adequate product liability indemnification insurance agreement. Supertex inc. does not assume responsibility for use of devices described, and limits its liability to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions and inaccuracies. Circuitry and specifications are subject to change without notice. For the latest product specifications refer to the Supertex inc. (website: http//www.supertex.com) 00 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited. Doc.# DSFP-HV86 B00 MIN 0.70 0.00 0.8.8*.0.8*.0 0.0 0.00 0 O 0.0 0.0 NOM 0.7 0.0 0..00.6.00.6 0.0 REF BSC - - MAX 0.80 0.0 0.0.*.80.*.80 0. 0. O JEDEC Registration MO-0, Variation WEED-, Issue K, June 006. * This dimension is not specified in the JEDEC drawing. This dimension differs from the JEDEC drawing. Drawings not to scale. Supertex Doc. #: DSPD-6QFNK7XP00, Version C000. 7 Supertex inc. Bordeaux Drive, Sunnyvale, CA 08 Tel: 08--8888 www.supertex.com