MT8940

Features:

• Provides T1 clock at 1.544 MHz locked to input frame pulse
• Sources CEPT (30+2) Digital Trunk/ST-BUS clock and timing signals locked to internal or external 8 kHz signal
• TTL compatible logic inputs and outputs
• Uncommitted 2-input NAND gate
• Single 5 volt power supply
• Low power ISO-CMOS technology


Application

• Synchronization   and   timing   control   for T1 and CEPT digital trunk transmission links
• ST- BUS clock and frame pulse source


Pinout




Specifications

	Parameter	Symbol	Min	Max	Units
1	Supply Voltage	VDD	-0.3	7.0	V
2	Voltage on any pin	VI	VSS-0.5	VDD+0.5	V
3	Input/Output Diode Current	IIK/OK		±10	mA
4	Output Source or Sink Current	IO		±25	mA
5	DC Supply or Ground Current	IDD/ISS		±50	mA
6	Storage Temperature	TST	-65	150	°C
7	Package Power Dissipation	PD		600	mW

Description

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 of MT8940 for the CEPT transmission link and the ST-BUS are provided by the second PLL loc-ked to an internal or an external 8 kHz frame pulse signal.

The MT8940 is fabricated in MITEL's ISO-CMOS technology.