ModemModule Developer’s Guide
MT3334SMI Design Considerations
This section discusses hardware considerations, PC board layout considerations, and Telecom labeling requirements.
Hardware Considerations
Disclaimer:
C2220PF/2KV
TIP
RINGR1
FB2
FB1
J1
x6
x5
4
3
x2
x 1
Loaded 4 Pin Modjack
C1220PF/2KV
Figure 1-7. Tip and Ring Ferrite Connections
EMC: Surface mount ferrites are used on T&R (Tip and Ring) to mitigate emission levels out the RJ- 11 cable. 220pF capacitors are also used on T&R to reduce the common mode emissions that may be present in certain systems. The ferrite and capacitors also aid in reducing the effects of transients that may be present on the line.
Recommended Ferrite
Manufacturer – Associated Component Technology (ACT)
Part # -
Manufacturer – Murata Erie
Part # - BLM31A601SPT
Recommended Capacitor |
|
Manufacturer – Murata Erie | Manufacturer - Ever Grace Electronic Industrials |
Part # - | Part # - YP221K2EA7PS |
Part # - |
|
Note: The capacitors used on T&R must have a Y2 safety rating.
Telecom: The
Recommended Connector
Manufacturer – Stewart
Part # -
Recommended Fuse
Manufacturer – RayChem
Part # -
Note: The fuse is also needed to meet UL1950 3rd edition protection against overvoltage from power line crosses.
14 | MT3334SMI |