1893AFLF IDT, 1893AFLF Datasheet - Page 27

• Manufacturer Part Number: 1893AFLF
• Description: Ethernet ICs 3.3V 10/100 BASE TX INTEGRATED PHYCEIVER
• Manufacturer: IDT
• Type: Integrated PHY Transceiverr

Specifications of 1893AFLF

• Rohs: yes
• Product: Ethernet Transceivers
• Data Rate: 10 Mb/s, 100 Mb/s
• Supply Voltage - Max: 3.47 V
• Supply Voltage - Min: 3.14 V
• Maximum Operating Temperature: + 70 C
• Package / Case: SSOP-48
• Ethernet Connection Type: 100Base-TX, 10Base-T
• Maximum Supply Current: 160 mA
• Minimum Operating Temperature: 0 C
• Standard Supported: 802.3
• Part # Aliases: ICS1893AFLF

6.3.1 Twisted-Pair Transmitter Interface
ICS1893AF, Rev. D 10/26/04
The twisted-pair transmitter driver uses an H-bridge configuration. ICS suggests any of the following 1:1
10/100 Magnetics:
•
•
Figure 6-1
•
•
•
Note:
1. If the transmit transformer has a choke, it may be put on the chip side, the RJ-45 side, or both.
2. Keep all TX traces as short as possible.
3. When making board traces, 50 -characteristic impedance is desirable.
Figure 6-1. ICS1893AF Transmit Twisted Pair
ICS1893AF
Halo TG22S012ND
Midcom 6120-37
Two 61.9
form a network that connects across both the transformer and the ICS1893AF TP_TXP and TP_TXN
pins.
The ICS1893AF supplies the power to the transformer. (No VDD connection is required.)
The ICS1893AF TP_CT pin is connected directly to the transformer transmit center tap connection and
is bypassed to ground with a 100-pF capacitor. The transformer center tap must not connect to the
resistor/inductor network.
TP_TXN 13
TP_TXP 12
ICS1893AF Data Sheet - Release
TP_CT 10
shows the design for the ICS1893AF twisted-pair transmitter interface.
Ideally, for these traces Z
1% resistors are in series, with a 120-nH 5% inductor between them. These components
Copyright © 2004, Integrated Circuit Systems, Inc.
61.9 1%
61.9 1%
120 nH
o
System Ground Plane
= 50 .
All rights reserved.
27
Center
Tap
1:1
100 pF
Chassis Ground Plane
75
0.1 F
Separate Ground Plane
Chapter 6 Interface Overviews
To RJ-45
October, 2004