HV850

Vdd, Supply Voltage ..................-0.5V to 4.5V
Operating Temperature.......... -25 to +85
Storage Temperature............ -65 to +150
Power Dissipation MSOP-8................. 300mW
*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.

Supertex HV850 is a high voltage electroluminescent (EL) Lamp Driver IC. It is designed to drive EL lamps of up to 2.0in², with capacitive values up to 4.5nF. It 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, HV850 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.

The EL lamp frequency can be set either by an external resistor REL or by applying an external clock where the clock frequency is divided by 128 to set the EL lamp frequency.