ICS1893 Integrated Circuit Systems, ICS1893 Datasheet - Page 124

• Manufacturer Part Number: ICS1893
• Description: 3.3-V 10Base-T/100Base-TX Integrated PHYceiver
• Manufacturer: Integrated Circuit Systems

10.3 Recommended Component Values
ICS1893 Rev C 6/6/00
VDD
Table 10-3.
† There are two IEEE Std 802.3 requirements that drive the tolerance for the frequency of the oscillator.
Note:
Figure 10-1. ICS1893 10TCSR and 100TCSR
Oscillator Frequency
10TCSR Resistor Value
100TCSR Resistor Value
LED Resistor Value
•
•
Clause 22.2.2.1 requires the MII TX_CLK to have an accuracy of ± 100 ppm.
Clause 24.2.3.4 is more stringent. It requires the code-bit timer to have an accuracy of 0.005% (that is, ±50 ppm).
ICS1893 Data Sheet - Release
Although the 10TCSR and 100TCSR pins do not need to be bypassed, include placeholders for
bypass capacitors on a printed circuit board that uses the ICS1893.
Parameter
VDD
7
Recommended Component Values for ICS1893
Copyright © 2000, Integrated Circuit Systems, Inc.
All rights reserved.
Minimum
10TCSR
2.0K 1%
510
–
–
–
Leave place holder but do not install bypass capacitors.
10TCSR
See
9
Typical
Figure 10-1
2.00k
ICS1893
124
25
1k
12.1 K
Maximum
1%
100TCSR
1.54K 1%
10k
Chapter 10 DC and AC Operating Conditions
–
–
–
100TCSR
10
± 50 ppm †
Tolerance
1%
1%
–
Units
June, 2000
MHz