DS21448L+ Maxim Integrated Products, DS21448L+ Datasheet - Page 36

• Manufacturer Part Number: DS21448L+
• Description: IC LIU QUAD E1/T1/J1 128-LQFP
• Manufacturer: Maxim Integrated Products
• Type: Line Interface Units (LIUs)r

Specifications of DS21448L+

• Number Of Drivers/receivers: 4/4
• Protocol: T1/E1/J1
• Voltage - Supply: 3.135 V ~ 3.465 V
• Mounting Type: Surface Mount
• Package / Case: 128-TQFP, 128-VQFP
• Product: Framer
• Number Of Transceivers: 4
• Supply Voltage (max): 3.465 V
• Supply Voltage (min): 3.135 V
• Supply Current (max): 400 mA
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

TRANSMIT LINE
RECEIVE LINE
Figure 7-1. Basic Interface
NOTE 1: ALL RESISTOR VALUES ARE ±1%.
NOTE 2: IN E1 APPLICATIONS, THE R
NOTE 3: THE RR RESISTORS SHOULD EACH BE SET TO 60Ω IF THE INTERNAL RECEIVE-SIDE TERMINATION FEATURE IS ENABLED. WHEN THIS
NOTE 4: SEE
(Table
FEATURE IS DISABLED, R
Table 7-A
7-A). NO RETURN LOSS IS REQUIRED FOR T1 APPLICATIONS.
AND
TOWARD THE NETWORK)
Table 7-B
(LARGER WINDING
R
= 37.5Ω FOR 75Ω OR 60Ω FOR 120Ω E1 SYSTEMS, OR 50Ω FOR 100Ω T1 LINES.
T
FOR THE APPROPRIATE TRANSMIT TRANSFORMER TURNS RATIO (N).
2:1
1:1
RESISTORS ARE USED TO INCREASE THE TRANSMITTER RETURN LOSS
R
r
R
R
t
t
(NONPOLARIZED)
R
0.1µF
r
1.0µF
36 of 60
RTIP
TTIP
RRING
TRING
Semiconductor
DS21448
Dallas
DS21448 3.3V T1/E1/J1 Quad Line Interface
MCLK
V
V
V
V
DD
DD
SS
SS
0.01µF
(THIS CAN ALSO BE 1.544MHz
FOR T1 ONLY OPERATION)
0.1µF
0.1µF
2.048MHz
0.01µF
V
10µF
DD
+
68µF