Features
■ AC or DC input
■ Programmable sense voltage
■ Logic level compatibility
■ Threshold guaranteed over temperature (0°C to 70°C)
■ Optoplanar™ construction for high common mode immunity
■ UL recognized (file # E90700)
■ VDE certified – ordering option ‘V’, e.g., HCPL3700V

Applications
■ Low voltage detection
■ 5 V to 240 V AC/DC voltage sensing
■ Relay contact monitor
■ Current sensing
■ Microprocessor Interface
■ Industrial controls

Description
The HCPL-3700 voltage/current threshold detection optocoupler consists of an AlGaAs LED connected to a threshold sensing input buffer IC which are optically coupled to a high gain darlington output. The input buffer chip is capable of controlling threshold levels over a wide range of input voltages with a single resistor. The output is TTL and CMOS compatible.