Vishay tsop ir receiver modules for remote control systems vishay tsop31233 a miniaturised infrared receiver module with a carrier frequency of 33khz that has been designed for remote control systems a pin diode and a preamplfier are assembled on a lead frame with the epoxy package acting as an ir filter the demodulated output signal can be directly connected to a microprocessor for decoding the module is optimised to suppress most spurious pulses from energy saving lamps such as cfls vis