The TDA5051A is a modem IC, specifically dedicated to ASK transmission by means of the home power supply network, at 600 baud or 1200 baud data rate. It operates from a single 5 V supply
Transmission and reception stages are controlled either by the master clock of the microcontroller or by the on-chip reference oscillator connected to a crystal. This ensures the accuracy of the transmission carrier and the exact trimming of the digital filter, thus making the performance totally independent of application disturbances such as component spread, temperature, supply drift.
Transmission mode – To provide strict stability with respect to environmental conditions, the carrier frequency is generated by scanning the ROM memory under the control of the microcontroller clock or the reference frequency provided by the on-chip oscillator
Reception mode – The input signal received by the modem is applied to a wide range input amplifier with AGC (−6 dB to +30 dB). This is basically for noise performance improvement and signal level adjustment, which ensures a maximum sensitivity of the ADC.