ICS1893AFT IDT, Integrated Device Technology Inc, ICS1893AFT Datasheet - Page 27

• Manufacturer Part Number: ICS1893AFT
• Description: PHYCEIVER LOW PWR 3.3V 48-SSOP
• Manufacturer: IDT, Integrated Device Technology Inc
• Series: PHYceiver™r
• Type: PHY Transceiverr

Specifications of ICS1893AFT

• Protocol: MII
• Voltage - Supply: 3.14 V ~ 3.47 V
• Mounting Type: Surface Mount
• Package / Case: 48-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Number Of Drivers/receivers: -
• Other names: 1893AFT; 800-1920-2; ICS1893AFT

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