CS8900A-IQZR Cirrus Logic Inc, CS8900A-IQZR Datasheet - Page 132

• Manufacturer Part Number: CS8900A-IQZR
• Description: Ethernet ICs IC 10Mbps Ethernet Controller 5V
• Manufacturer: Cirrus Logic Inc

Specifications of CS8900A-IQZR

• Ethernet Connection Type: 10Base- 2, 10Base- 5, 10Base- F, 10Base- T
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Product: Ethernet Controllers
• Standard Supported: IEEE 802.3
• Data Rate: 10 Mbps
• Maximum Operating Temperature: + 85 C
• Package / Case: LQFP-100
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.5 10BASE-T WIRING
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132
CS8900A
If a center tap transformer is used on the RXD+ and RXD- inputs, replace the pair of Rr re-
sistors with a single 2xRr resistor.
The Rt and Rr resistors are ±1% tolerance.
The CS8900A supports 100, 120, and 150 Ω unshielded twisted pair cables. The proper val-
ues of Rt and Rr, for a given cable impedance, are shown below:
Note: for 3.3V operation the turns ratio on TXD+ and TXD- is 1:2.5, rt is 8
and the 68pF cap changes to 560pF.
+
-
TXD +
TXD -
RXD+
RXD-
Cable Impedance (Ω)
Rt
Rt
0.01 μ F
100
120
150
CIRRUS LOGIC PRODUCT DATASHEET
0.01 μ F
68 pF
Rr
Rr
Rt (Ω)
24.3
30.1
37.4
1 :
1 : 1
2
Crystal LAN™ Ethernet Controller
RD +
Rr (Ω)
TD +
RD -
TD -
49.9
60.4
75
1
2
3
6
Ω
for 100
RJ45
CS8900A
Ω
DS271F5
cable