The MT8940 is a dual digital phase-locked loop providing the timing and synchronization signals for the T1 or CEPT transmission links and the ST-BUS. The first PLL provides the T1 clock (1.544 MHz) synchronized to the input frame pulse at 8 kHz. The timing signals for the CEPT transmission link and the ST-BUS are provided by the second PLL locked to an internal or an external 8 kHz frame pulse signal. The MT8940 is fabricated in MITEL's ISO-CMOS technology.