PCA EPE6268G

10 Base-T Module with Enhanced
CMRR for PC Card Applications
ELECTRONICS INC.
EPE6268G
• Optimized Resistor Network for Wider Range Voltage Template •
• Recommended for NSC , ATT & SMC 91C94 •
• Superior Common Mode Attenuation •
• Complies with or exceeds IEEE 802.3, 10 Base-T Requirements •
Electrical Parameters @ 25° C
Cut-off
Frequency
(MHz)
Insertion
Loss
(dB Max.)
Return
Loss
(dB Min.)
± 1.0
MHz
1-10
MHz
5-10
MHz
Common Mode
Rejection
(dB Min.)
Attenuation
(dB Min.)
@ 20
MHz
@ 25
MHz
@ 30
MHz
@ 40
MHz
@ 30
MHz
@ 100
MHz
@ 200
MHz
@ 400
MHz
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
Xmit
Rcv
17
17
-1
-1
-20
-20
-5
-4
-11
-8
-15
-11
-25
-15
-40
-50
-35
-40
-35
-35
-20
-10
•
Isolation : meets or exceeds 802.3 IEEE Requirements • Characteristic Filter Impedance : 100 Ω •
• Referenced to the filter output @ 5 MHz for filter only, excluding resistor network •
Schematic
Receive Channel
3
7
49.9Ω
6
13
Transmit Channel
261Ω
60.4Ω
8
Differential Filter
Isolation
Common Mode Filter
Differential Filter
Isolation
Common Mode Filter
2
49.9Ω
14
1
12
9
5
60.4Ω
Chip Side
4
10
261Ω
Chip Side
Media Side
Dimensions
Package
A
N
Dim.
Min.
A
B
C
D
E
F
G
H
I
J
K
L
M
N
P
Q
.780
.510
.074
.595
.003
.097
.660
.017
.008
.090
0°
.025
---------
N
J
Pin 1
I.D.
PCA
EPE6268G
Date Code
B
Pad
Layout
Q
E
C
K
L
PCA ELECTRONICS, INC.
16799 SCHOENBORN ST.
NORTH HILLS, CA 91343
P
M
D
H
Media Side
F
(Inches)
Max. Nom.
.800
.530
.084
.605
.010
.103
.680
.022
.013
.100
8°
.045
---------
.790
.520
.079
.600
.005
.100
.670
.020
.011
.095
4°
.040
.030
.200
.085
.700
(Millimeters)
Min. Max. Nom.
19.81
12.96
1.88
15.11
.076
2.46
16.76
.432
.203
2.29
0°
.635
---------
20.32
13.46
2.13
15.37
.254
2.62
17.27
.559
.330
2.54
8°
1.14
---------
20.07
13.21
2.01
15.24
.127
2.54
17.02
.508
.279
2.41
4°
1.02
.762
5.08
2.16
17.78
I
G
CSE6268Ga Rev. 1
9/28/98
Product performance is limited to specified parameters. Data is subject to change without prior notice.
TEL: (818) 892-0761
FAX: (818) 894-5791
http://www.pca.com
10 Base-T Module with Enhanced
CMRR for PC Card Applications
ELECTRONICS INC.
EPE6268G
The circuit below is a guideline for interconnecting PCA’s EPE6268G with SMC 91C94 chip as a reference controller.
Further details of system design, such as chip pin-out, etc. can be obtained from the specific chip manufacturer.
Typical insertion loss of the isolation transformer/filter is 0.7dB. This parameter covers the entire spectrum of the encoded
signals in 10 Base-T protocols. However, the predistortion resistor network introduces some loss which has to be taken
into account in determining how well your design meets the Standard Template requirements.
A quick calculation of the effective Thevenin’s termination impedance for the filter follows: /R(termination) = 2x(65//265) i.e.
approximately 100Ω.
Thus, when measuring the return loss of these parts on the bench, it is therefore, necessary to provide a shunting resistor
of approximately 5Ω representing the four 5Ω output signal sources from the PHY chip.
The phantom resistors shown around the RJ45 connector have been known to suppress unwanted radiation that unused
wires pick up from the immediate environment. Their placement and use are to be considered carefully before a design is
finalized.
It is recommended that there be a neat separation of ground planes in the layout. It is generally accepted practice to limit
the plane off at least 0.08 inches away from the chip side pins of EPE6268G. There need not be any ground plane beyond
this point.
For best results, PCB designer should design the outgoing traces preferably to be 50Ω, balanced and well coupled to
achieve minimum radiation from these traces.
Typical Application Circuit for UTP PC Card
TX+
TXd+
Card Bus
for
10 Base-T
PHY
TXTXdRX+
RX-
5
4
6
7
TX+
9
1
8
2 TX-
14
3
13
6
1
RX+
RJ45*
RX4
5
7
8
3
EPE6268G
12
10
Chassis
Ground
Notes : * Pin-outs shown are for NIC configurations.
PCA ELECTRONICS, INC.
16799 SCHOENBORN ST.
NORTH HILLS, CA 91343
CSE6268Gb Rev. 1 9/28/98
TEL: (818) 892-0761
FAX: (818) 894-5791
http://www.pca.com