Analog microchip HV816

HV816 is a high voltage Electroluminescent (EL) lamp driver designed for driving a lamp capacitance of up to 150nF, or an area of approximately 42 square inches. It is comprised of a boost converter followed by an H-bridge. The boost converter produces a regulated output voltage, which is set at a nominal value of 180V using an internal reference voltage. The H-bridge is used to produce a differential output drive and the EL lamp will therefore see ±180V (360V peak-to-peak). The HV816 has two internal oscillators, one for controlling the boost converter switching frequency and the other for controlling the H-bridge switching frequency. Having separate control of each switching frequency allows flexibility in the circuit design. The operating input supply voltage is 2.7 to 5.5V, but the Enable (EN) and Select (SEL) interface to the device will accept logic high levels down to 1.5V. The EN input is for turning the device ON and OFF. The SEL input is for external logic control of the H-bridge switching frequency, if required. The HV816 boost converter stage uses a single inductor and a minimum number of external components. The input voltage to the inductor can be different from the input voltage to the HV816 (split supply). The external inductor is connected either between the LX and VDD pins or, for split supply applications, between the LX pin and a higher voltage supply (shown as VIN in the Block Diagram).