MIC4827YMM [Microchip]

MIC4827 is a high output voltage, DC to AC converter, designed for driving electroluminescent (EL) lamps. The device operates from an input voltage range of 1.8V to 5.5V, making it suitable for 1-cell Li-Ion and 2- or 3-cell alkaline/NiCad/NiMH battery applications. The MIC4827 converts a low voltage DC input to a 180VPP AC output signal that drives the EL lamp. The MIC4827 is comprised of two stages: a boost stage, and an H-bridge, lamp driver stage. The boost stage steps the input voltage up to +90V. The H-bridge stage then alternately switches the +90V output to each terminal of the EL lamp, thus creating a 180VPP AC signal to drive the EL lamp and generate light. The MIC4827 features separate oscillators for the boost and H-bridge stages. External resistors independently set the operating frequency of each stage. This flexibility allows the EL lamp circuit to be optimized for maximum efficiency and brightness. The MIC4827 uses a single inductor and a minimum number of external components, making it ideal for portable, space-sensitive applications. The MIC4827 is available in an 8-pin MSOP package with an ambient temperature range of -40°C to +85°C.

• 1.8V to 5.5V DC input voltage
• 180VPP regulated AC output waveform
• Independently adjustable EL lamp frequency
• Independently adjustable boost converter frequency
• 0.1µA shutdown current