ADAPTIVE DC BIAS COMPENSATION FOR A/D CONVERTERS
Original Publication Date: 1989-Aug-01
Included in the Prior Art Database: 2001-Nov-08
In telecommunications applications, it is often necessary to transmit very low frequency information for sub audible signaling and data which requires DC coupling of circuit stages or large coupling capacitors, The response time to DC transient pulses should be kept at a minimum to allow recovery of the system after turn on of pulsed systems such as battery savers where the power supply line is strobed. To allow for transmission of sub audible information and fast recovery time for telecommunications systems using A/D conversion an adaptive system has been developed shown in figure 1 that reads the DC level of the input signal (without modula- tion) and stores that level digitally. Any DC level change caused by make tolerance or temperature change is nulled out.