Catalog
High Voltage, Low Noise, Inductorless EL Lamp Driver
Key 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
• + EL Lamp dimming
Description
AI
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 2.4 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.
