am7996 Advanced Micro Devices, am7996 Datasheet - Page 7

• Manufacturer Part Number: am7996
• Description: Ieee 802.3/ethernet/cheapernet Transceiver
• Manufacturer: Advanced Micro Devices

Figure 2 is an external component diagram showing
how to implement the transmit mode collision detect
levels recommended by IEEE 802.3. Figure 3 on the
following page shows how to implement the receive
mode collision detect levels recommended by
IEEE 802.3. Receive mode collision detect threshold
Notes:
1.
2.
3.
4.
6.
7.
5.
PE64102/PE64107 (or equivalent)
COLL
RCV
XMT
C
D2 can be eliminated in Cheapernet (IEEE 802.3, 10BASE2) applications.
Shown with SQE Test disabled.
Discrete Power Supply or Hybrid-Hybrid DC-DC Converter Manufacturers include:
The capacitance of C3, Am7996 package, D3 and the printed circuit board should add up to 180 pF 20%.
The capacitance of C1, Am7996 package and the printed circuit board should add up to 39 pF.
Figure 2 used for production testing of all parameters that are tested.
L
is the effective load capacitance across R6; C
Ethernet (IEEE 802.3, 10BASE5)
Reliability: 2E12R9
Valor Electronics: PM1001
Cheapernet (IEEE 802.3, 10BASE2)
Reliability Inc: 2VP5U9
Valor Electronics: PM7102
Power (DTE)
Figure 2. Am7996 External Component Diagram for Transmit Mode Collision Detect
(75 H)
1:1
1:1
1:1
MAU Power Supply
(Note 4)
40.2
40.2
1%
1%
R1
R2
–9 V
GND
174
1%
R3
(Note 3)
10
1
4
5
6
8
2
3
7
9
C
CI–
DI–
DI+
DO–
CI+
VC REF
DO+
V CC1
SQE^TEST
V EE
is the compensation capacitance (C
Am7996
Am7996
COLL OSC
levels of the Am7996 are implemented by adding R9,
R10 and C4. For the values of the components shown in
Figure 3, a nominal receive mode collision detect
threshold of –1.5 V, for a –1.404 V to –1.581 V window,
is achieved.
V COL
V CC2
Shield
V TX+
V TX-
RXT
TXT
Tap
NC
NC
19
18
17
16
15
14
13
12
20
11
1%
9.09
R8
1%
(Note 5)
1.1 k
180 pF
R4
(Note 6)
(Note 1)
39 pF
C L
C3
C
C1
= 1/3 C
24.9 k
0.1 F
1N4001
D3
9.09
L
1%
C2
R6
).
1%
R7
(Note 2)
C C
Connector
75 k
D2
1%
Coax
R5
(Note 1)
1N4150
AMD
07506E-5
D1
7