The MLX10420 from Melexis is a triple air-core gauge driver with serial interface. The IC (integrated circuit) can drive up to three air-core meters—two 360° meters and one 90° meter. A microprocessor peripheral for air-core meter control, the MLX10420 has SIN/COS PWM (pulse width modulation) drivers and serial commands. The circuit controls two independent sets of CMOS (complementary metal oxide semiconductor) power bridges. A power-on self test detects open or short-circuit outputs for each air-core meter. A real-time angle tracking scheme avoids display errors. Communication with the microprocessor is done via a three-wire serial link. The MLX10420 offers a special output pin for a possible error status. Developed to meet the automotive market’s quality requirements, the IC can fit in meter applications for small cars, motorcycles, and retro-style dashboards.