ATA2516

The IC ATA2516 is a complete IR receiver for data communication systems. The device is developed and optimized for use in carrier frequency modulated transmission applications. Its function can be described using the block diagram in Figure 1 on page 2. The input stage meets two main functions. First, it provides a suitable bias voltage for the PIN diode. Secondly, the pulsed photo current signals are transformed into a voltage by a special circuit which is optimized for low noise application. After amplification by a Controlled Gain Amplifier (CGA), the signals pass a tuned integrated narrow bandpass filter with a center frequency f₀ equivalent to the chosen carrier frequency of the input signal. The demodulator is used to convert the input burst signal to a digital envelope output pulse and to evaluate the signal information quality, i.e., unwanted pulses will be suppressed at the output pin. All this is done by means of an integrated dynamic feedback circuit which varies the gain as a function of changing environmental conditions (ambient light, modulated lamps etc.). A 7-bit digital- to-analog converter is used to adjust the gain of the controlled gain amplifier. Other special features serve to adapt to the current application to secure best transmission quality. The ATA2516 operates in a voltage supply range of 4.5 V - 5.5 V.