MT8941 Datasheet, PDF (1/27 Pages) Mitel Networks Corporation – CMOS ST-BUS™ FAMILY Advanced T1/CEPT Digital Trunk PLL

MT8941B
Advanced T1/CEPT Digital Trunk PLL
Data Sheet
Features
• Provides T1 clock at 1.544 MHz locked to an 8
kHz reference clock (frame pulse)
• Provides CEPT clock at 2.048 MHz and ST-BUS
clock and timing signals locked to an internal or
external 8 kHz reference clock
• Typical inherent output jitter (unfiltered)= 0.07 UI
peak-to-peak
• Typical jitter attenuation at: 10 Hz=23 dB,100
Hz=43 dB, 5 to 40 kHz ≥ 64 dB
• Jitter-free “FREE-RUN” mode
• Uncommitted two-input NAND gate
• Low power CMOS technology
Applications
• Synchronization and timing control for T1
and CEPT digital trunk transmission links
• ST- BUS clock and frame pulse source
February 2005
Ordering Information
MT8941BE 24 Pin PDIP
MT8941BP 28 Pin PLCC
MT8941BPR 28 Pin PLCC
MT8941BP1 28 Pin PLCC*
MT8941BPR1 28 Pin PLCC*
Tubes
Tubes
Tape & Reel
Tubes
Tape & Reel
*Pb Free Matte Tin
-40°C to +85°C
Description
The MT8941B 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 MT8941B offers improved jitter performance over
the MT8940. The two devices also have some
functional differences, which are listed in the section on
“Differences between MT8941B and MT8940”.
F0i
C12i
MS0
MS1
MS2
MS3
C8Kb
C16i
Ai
Bi
DPLL #1
Mode
Selection
Logic
DPLL #2
2:1 MUX
Input
Selector
Clock
Generator
Variable
Clock
Control
Frame Pulse
Control
4.096 MHz
Clock
Control
2.048 MHz
Clock
Control
Yo
V_DD
V_SS
RST
Figure 1 - Functional Block Diagram
1
Zarlink Semiconductor Inc.
Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc.
Copyright 2003-2005, Zarlink Semiconductor Inc. All Rights Reserved.
CVb
CV
ENCV
F0b
C4b
C4o
ENC4o
C2o
C2o
ENC2o