HV852

www.DataSheet4U.com HV852 Initial Release High Voltage, Low Noise, Inductorless EL Lamp Driver Features ► No external components required when using an external EL clock frequency ► EL frequency can be set by an external resistor ► Low Noise ► DC to AC converter ► Drives up to 5.3nF (approx. 1.5in2 lamp) load ► Output voltage regulation ► Enable function General Description The Supertex HV852 is a high voltage, low noise, inductorless EL (electroluminescent) lamp driver. It is designed to drive EL lamps of up to 1.5in2, with capacitive values up to 5.3nF over an input voltage range of 2.4V to 5.0V. The HV852 converts a low voltage DC input to a high voltage AC output across an EL lamp. It uses a charge pump scheme to boost the input voltage eliminating the need for an external inductor, diode, and high voltage capacitor commonly found in conventional topologies. The charge pump circuit discharges its energy into an EL lamp through a high voltage H-bridge. Once the voltage reaches its regulated limit, it is turned off to conserve power. The EL lamp is then discharged to ground and the H-bridge changes state to allow the charge pump to charge the EL lamp in the opposite direction. Applications ► ► ► ► Cellular phone keypad Watches Small handheld wireless devices MP3 Players Typical Application Circuit HV852 + VDD CDD REL VDD REL EN CLKIN VA VB GND CLKEN EL LAMP VDD = ON GND = OFF EL Lamp frequency set by REL 1 HV852 Ordering Information Package Options DEVICE MSOP-...