Document
www.DataSheet4U.com
Token Ring Transceiver Module
ELECTRONICS INC.
EPT7055AM
• Optimized for voltage source driving into 150Ω • • Enhanced Common Mode performance over UTP • • Robust construction allows for solder reflow processes • • Complies with or exceeds IEEE 802.5 Requirements •
Electrical Parameters @ 25° C
Impedance (Ω) [Xmit/Rcv] Chip Side 150 100 1-16 MHz Insertion Loss (dB Max.) 32 MHz 36 MHz 44 MHz 1-8 MHz Return Loss (dB Min.) 8-17 MHz 17-24 MHz 1-30 MHz Common Mode Rejection (dB Min.) 30-100 MHz 100-200 MHz 200-300 MHz Rcv -17 -50 Crosstalk (dB Min.) 10 MHz
Cable Side Xmit Rcv Xmit Rcv Xmit Rcv Xmit Rcv Xmit Rcv Xmit -.6 -.5 -7 -1 -25 -3 -3.5 -3 -18 -23 -12
Rcv Xmit -20 -8
Rcv Xmit Rcv Xmit Rcv Xmit Rcv Xmit -10 -57 -40 -35 -35 -30 -29 -20
Schematic
TX1+ 2 150Ω TX1- 4 CT- 5 RX0+ 6 150Ω RX0- 8 RXCT 7 1 : .817 LPF 1 : .817 14 TXO+ 3.01KΩ .1 µF
DataShee
R1 13 TXO9 PHA 12 RX1+ UTP
DataSheet4U.com
4.75KΩ R2 .1 µF
11 RX110 PHB
Package
A B
Pin 1 I.D. PCA EPT7055AM Date Code Dim. A B C D E F G H I J Min. 1.480 .265 .450 1.300 .010 .100 .100 .020 .010° .135
Dimensions
(Inches) Max. Nom. 1.500 .275 .460 Typ. .015 .140 .120 .024 Typ. .140 (Millimeters) Min. Max. Nom. 37.85 6.73 11.43 33.02 .254 3.18 2.54 .508 .254 3.43 38.10 6.99 11.68 Typ. .381 3.56 Typ. .610 Typ. .356
C
E
H D
F
G
I J
DataSheet4U.com
PCA ELECTRONICS, INC. 16799 SCHOENBORN ST. NORTH HILLS, CA 91343
CST7055AMa Rev. A 6/11/97
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
DataSheet 4 U .com
www.DataSheet4U.com
Token Ring Transceiver Module
ELECTRONICS INC.
EPT7055AM
The circuit below is a guideline for interconnecting PCA’s EPT7055AM with a typical Token Ring PHY chip for 4 Mb/16Mb applications over UTP cable. Further details of system design should be obtained from the specific chip manufacturer. Note that this module is optimized for a “voltage source” driver such as TI380C60. Typical insertion loss of the isolation transformer is 0.5dB up to 16 MHz. Under terminated conditions, to transmit a 2V pkpk signal across the cable, you must adjust the specific chip preset template control resistors to get at least 2.12V pk-pk across the transmit input pins. Note that there is no need for the receiver side filtering. So consider this a cost effective solution for almost all Token Ring applications using this or similar chips. The pull down resistors to chassis via a cap shown around the RJ45 connector have been known to suppress unwanted radiation that unused wires pick up from the immediate environment. This is specially true if driving UTP cable. Their placement and use are to be considered carefully before a design is finalized. No specific recommendation is made here for phantom return circuitry: implementation varies. Please note that additional emission control has been observed if both nodes of the phantom bypass capacitor on the transmit channel are pulled to the chassis ground via suitable capacitors. 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 0.05 inches away from the chip side of EPT7055AM. 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.
et4U.com
DataSheet4U.com
Typical Application Circuit Connection to TI380C60 (or Equivalent)
RCVINA
150Ω
38
6 8
+5V
12 11 14 13
5 Xmit± 4 3 Rcv± 6 1 2 7 8
RCVINB
RJ45
37
+5V
PHOUTA PHOUTB
50Ω/2W
29
50Ω/2W
9
10µF 10µF
27
10
TMS38060
DROUTB DROUTA 32
100Ω
422Ω
31
100Ω
2
EPT7055AM
7 5
11
Common Mode
4
Notes : 1. Current limiting resistors R1 & R2 are included in this package.
DataSheet4U.com
PCA ELECTRONICS, INC. 16799 SCHOENBORN ST. NORTH HILLS, CA 91343
CST7055AMb Rev. A 6/11/97
TEL: (818) 892-0761 FAX: (818) 894-5791 http://www.pca.com
DataSheet 4 U .com
.