XR-2123 Datasheet | Exar

XR-2123/2123A PSK ModulatorIDemodulator GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAMS This series of devices provide the modulator and demodulator for phase-shifted keyed modulated signals. The devices have an on-chip digital-to-analog converter, allowing digital external programming of Bell 212A, CCITT V.22 or V.26 functions. The XR-2123 provides the modulator and demodulator functions. It is adequate for Bell 212A (1200 BPS only) and Bell 201 standards. The XR-2123 requires a synchronous-to-asynchronous converter and scrambler-descrambler for the digital portion of the modem for 212A applications. Level shifters and filtering is required for the analog portion. The X R-2123A provides...