Cirrus Logic AN83 - Manual (Page 20)

AN83
20 AN83REV3
Component Placement and Signal Routing
Please refer to “Layout Considerations for the
CS8900A” on page 35 of this document for more
details on the placement of components on the
board. It is important to provide very clean and ad-
equate +5 V and ground connections to the
CS8900A.
Bill of Material
Table 1 has a list components that are typically
used to assemble this adapter card. For most of the
components, there are several alternative manufac-
turers.
1
2
3
4
5
6
7
8
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
9
10
11
12
13
14
15
16
(1-3) (16-14) 1:1
(6-8) (11-9) 1:1.414
10 BaseT Transformer
100
R2
24.3
R4
24.3
R5
68 pF
C30
.1 µF
C23
Do Not
Populate
.1 µF 2KV
C29
.1 µF 2KV
C28
J1
10
8
7
6
5
4
3
2
1
9
.1 µF
Do Not
Populate
10BT_RD-
10BT_RD+
10BT_TD-
10BT_TD+
Figure 10. 10BASE-T Schematic 5V
C17
TANT TANT TANT
22 µF 22 µF 22 µF
C16 C15 +
+5V
GND
+ +
Figure 11. Decoupling Capacitors Schematic
Item Reference # Description Quantity Vendor Part Number
1 C2, C5, C7..C14 Capacitor, 0.1 µF, X7R, SMT0805 10
2 C15, C16, C17 Capacitor, 22 µF, SMT7343 3
3 R2, R3 Resistor, 24.3, 1%, 1/8W, SMT0805 2
4 R1 Resistor, 100, 1%, 1/8W, SMT0805 1
5 R4 Resistor, 4.99K, 1%, SMT0805 1
6* X1 Crystal, 20.000 MHz 1 M-tron ATS-49,20.000 MHz,18 pF
7 J1 Connector, RJ45, 8 pin 1 AMP 555164-1
8 T1 Transformer, 2, 1:1, 1:1.41 1 Valor ST7011 (SOIC)
9 U1 ISA Ethernet Controller 1 Crystal CS8900A
10* U3 1K EEPROM 1 Microchip 93C46 (8 pin SOIC)
* Depending on system resources, these parts may not be needed.
Table 1. CS8900A Design Bill of Materials