MT9042C Mitel Networks Corporation, MT9042C Datasheet - Page 16

• Manufacturer Part Number: MT9042C
• Description: Multitrunk System Synchronizer
• Manufacturer: Mitel Networks Corporation

MT9042C
When 10 Normal to Holdover to Normal mode
change sequences occur without MTIE enabled, and
in each case holdover was entered for 2s, each
mode change sequence could still account for a
phase change as large as 350ns. However, there
would be no accumulated phase change, since the
input to output phase is re-aligned after every
Holdover to Normal state change. The overall MTIE
would only be 350ns.
Reset Circuit
A simple power up reset circuit with about a 50us
reset low time is shown in Figure 15. Resistor R
for protection only and limits current into the RST pin
during power down conditions. The reset low time is
not critical but should be greater than 300ns.
16
To Line 1
To Line 2
TX Line
TX Line
RX Line
RX Line
XFMR
XFMR
XFMR
XFMR
Figure 14 - Dual T1 Reference Sources with MT9042C in 1.544MHz Automatic Control
To
To
To
To
TTIP
TRING
RTIP
RRING
TTIP
TRING
RTIP
RRING
MT9074
MT9074
MT8985
E1.5o
E1.5o
DSTo
DSTo
STo0
STo1
DSTi
DSTi
LOS
LOS
STi0
STi1
C4i
C4i
C4i
F0i
F0i
F0i
P
is
+ 5V
1k
MT9042C
10nF
10k
SEC
Figure 15 - Power-Up Reset Circuit
TRST
RST
PRI
LOS1
LOS2
MS1
MS2
RSEL
MT9042C
RST
OSCi
+ 5V
C4o
C2o
FS1
FS2
GTo
F0o
GTi
+ 5V
Advance Information
1k
R
10k
Out
P
150k
20MHz 32ppm
R
1k
1k
CLOCK
+5V
10uF
10nF
C
+