The Analog Devices DS21Q59L is a quad E1 transceiver IC designed for telecom applications. It features 4 complete E1 transceivers and operates on 3.3V low-power CMOS technology.
The Analog Devices / Maxim Integrated DS21Q58L is an E1 Quad Transceiver designed for telecom applications. It operates within a 3.14V to 3.47V supply range and features a 100-LQFP package.
The DS21Q50L+ is a quad E1 transceiver from Analog Devices / Maxim Integrated, designed for telecom applications. It operates at 3.3V and comes in a 100-LQFP package.