HC5523 LSSGR/TR57 CO/Loop Carrier SLIC with Low Power Standby is interchangeable with Ericsson's PBL3764A/4 for distributed central office applications. The product has good hot-plug resistance and can resist false triggering in the presence of long currents. HC5523 is fabricated in a High Voltage Dielectrically Isolated (DI) Bipolar Process that eliminates leakage currents and device latch-up problems normally associated with junction isolated ICs. The elimination of the leakage currents results in improved circuit performance for wide temperature extremes. The latch free benefit of the DI process guarantees operation under adverse transient conditions. This process feature makes the HC5523 ideally suited for use in harsh outdoor environments.