DS21458-W+ Maxim Integrated, DS21458-W+ Datasheet - Page 173

• Manufacturer Part Number: DS21458-W+
• Description: Network Controller & Processor ICs
• Manufacturer: Maxim Integrated

Specifications of DS21458-W+

• Product: Framer
• Number Of Transceivers: 4
• Data Rate: 64 Kbps
• Supply Current (max): 328 mA
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Package / Case: CSBGA
• Minimum Operating Temperature: 0 C
• Operating Supply Voltage: 3.3 V
• Supply Voltage - Max: 3.465 V
• Supply Voltage - Min: 3.135 V
• Part # Aliases: 90-21458+W00

25.8 Recommended Circuits
Figure 25-5. Software-Selected Termination, Metallic Protection
Table 25-6. Component List (Software-Selected Termination, Metallic
Protection)
75/100/110/120 
Twisted Pair/Coax
75/100/110/120 
Twisted Pair/Coax
Design Notes:
1
2
Choke is optional but should be included when necessary for common mode noise reduction.
Decoupling capacitors need to be placed near device power pins
Note 1:
Note 2:
Note 3:
Note 4:
T1 and T2
T3 and T4
F1 and F2
S1 and S2
S3 andS4
NAME
T3 and T4 are optional. For more information, contact the Telecom Support Group at
[e-mail].
The layout from the transformers to the network interface is critical. Traces should be at least 25
mils wide and separated from other circuit lines by at least 150 mils. The area under this portion
of the circuit should not contain power planes.
Some T1 (never in E1) applications source or sink power from the network-side center taps of
the Rx/Tx transformers.
A list of transformer part numbers and manufacturers is available by contacting
[e-mail].
F1
F2
1.25A slow blow fuse
25V (max) transient suppressor
77V (max) transient suppressor
Transformer 1:1CT and 1:2CT (3.3V, SMT)
Dual common-mode choke (SMT)
S3
S4
T3
T4
1
1
2:1
1:1
T2
T1
DESCRIPTION
173 of 269
60 
S1
S2
1.0 F
0.1 F
60 
DS21455/DS21458 Quad T1/E1/J1 Transceivers
TTIP
TRING
RTIP
RRING
Dallas Semiconductor
T1/E1/J1 SCT or LIU
DVDD
DVSS
TVDD
TVSS
RVDD
RVSS
0.01 F
0.1 F
0.1 F
2
2
2
VCC
VCC
VCC
0.1 F
68 F
2
2