This reference design is intended for use in molded case circuit breakers (MCCB) electronic trip units. The op amp based design acts as current monitoring for over-current earth fault relays. Utilizing a low cost op amp, this design provides a pick-up (A) accuracy ±10 % and time delay (s) accuracy 0 to -20%. Additionally, this design takes harsh environment conditions in mind with features such as ambient insensitivity from -10 to 70°C and high electromagnetic immunity. Finally the analog front end of this design seemlessly interfaces to TI MSP430 MCU for quicker evaluation and faster time-to-market.
- Pick-up accuracy at ±10 % and time delay accuracy at 0 to -20% offer wide range of adjustment for maximum flexibility
- Ambient insensitivity from -10 to +70°C for global design and worldwide acceptance
- Excellent trip time repeatability
- Wide input DC-DC converter with under voltage and overcurrent protection
- Self-power (CT powered) supply with reduced CT loading and Power loss
- Robust design that prevents phase reversal in overdrive conditions and high electrostatic discharge (ESD) protection (4-kV HBM)