The TOIM4232 Endec IC provides proper pulse shaping for the SIR IrDA front end infrared transceivers as of the 4000-series. For transmitting the TOIM4232 shortens the RS232 output signal to IrDA compatible electrical pulses to drive the infrared transmitter. In the receive mode, the TOIM4232 stretches the received infrared pulses to the proper bit width depending on the operating bit rate. The IrDA bit rate varies from 2.4 kbit/s to 115.2 kbit/s. The TOIM4232 is using a crystal clock 3.6864 MHz for its pulse stretching and shortening. The clock can be generated by the internal oscillator. An external clock can be used, too. The TOIM4232 is programmable to operate from 1200 bit/s to 115.2 kbit/s by the communication software through the RS232 port. The output pulses are software programmable as either 1.627 s or 3/16 of bit time. The typical power consumption is very low with about 10 mW in operational state and in the order of a few microwatts in standby mode.