IDT77V1254L25PG IDT, Integrated Device Technology Inc, IDT77V1254L25PG Datasheet - Page 33

• Manufacturer Part Number: IDT77V1254L25PG
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of IDT77V1254L25PG

• Data Rate: 25.6/51.2Mbps
• Number Of Channels: 4
• Type Of Atm Phy Interface: DPI/UTOPIA
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 3.6V
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Pin Count: 144
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Not Compliant

Line Side (Serial) Interface
PHY to Magnetics Interface
ated in order to meet the launch amplitude specified by the standards. The external receive circuitry is designed to attenuate low frequencies in order
to compensate for the high frequency attenuation of the cable.
false signals in the absence of a real signal. This can be important because the 77V1254L25 does not disable error detection or interrupts when an
input signal is not present.
25.6 Mbps. Refer to Table 5 for the recommended magnetics.
IDT77V1254L25
Each of the four ports has two pins for differential serial transmission, and two pins for differential serial receiving.
A standard connection to 100 and 120 unshielded twisted pair cabling is shown in Figure 36. Note that the transmit signal is somewhat attenu-
Also, the receive circuitry biases the positive and negative RX inputs to slightly different voltages. This is done so that the receiver does not receive
When connecting to UTP at 51.2 Mbps, it is necessary to use magnetics with sufficient bandwidth. Such a device can also operate satisfactorily at
1
2
3
4
5
6
7
8
7
8
10
9
14
3
Magnetics
R1
R2
R3
R4
R5
R6
R7
R8
R9
Figure 36 Recommended Connection to Magnetics
Component
4
13
Table 4 Analog Component Values (Part 1 of 2)
AGND
5
12
AGND
16
15
1
2
33 of 48
47
47
620
110
2700
2700
82
33
33
R3
R8
C2
C1
R9
Value
R1
R2
±5%
±5%
±5%
±5%
±5%
±5%
±5%
±5%
±5%
R5
R4
R6
AVDD
AGND
Tolerance
R7
L1
TxD-
TxD+
RxD+
RxD-
IDT77V1253
IDT77V1254
3505 drw 36
.
December 2004