10 Base-T Interface Module for Multiport Applications ELECTRONICS INC. EPE6104 • Optimized for National DP83950B Repeater Chip • • Robust design allows for the toughest soldering processes • • 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 @ 50-70 MHz @ 50 MHz @ 100 MHz Crosstalk (dB Min.) @ 200 MHz @ 1-10 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 -15 -15 -7 -5 -18 -11 -37 -15 -40 -35 -50 -50 -50 -50 -25 -25 -45 -45 • Isolation : meets or exceeds 802.3 IEEE Requirements • Characteristic Filter Impedance : 100 Ω • • Referenced @ 5 MHz • All Resistors are matched within ± 1% • Schematic 332Ω 1 Transmit Channel 56Ω 2 Receive Channel 16 9 8 LPF 100Ω 3 100Ω 11 6 1:1 56Ω LPF 100Ω 4 1:1 14 332Ω 7 7 Chip Side UTP Side Chip Side UTP Side Package Dimensions A B C Pin 1 I.D. PCA EPE6104 Date Code E H J K L F I Dim. Min. (Inches) Max. A B C D E F G H I J K L 1.220 .310 .400 1.100 .020 .100 .165 .018 .010° .065 .120 .200 1.240 .330 .430 Typ. .023 Typ. Typ. .022 Typ. Typ. .140 Typ. (Millimeters) Min. Max. 9 Plcs 30.99 7.87 10.16 27.94 .508 2.54 4.19 .457 .254 1.65 3.05 5.08 31.50 8.38 10.92 Typ. .584 Typ. Typ. .559 Typ. Typ. 3.56 Typ. 9 Plcs G D PCA ELECTRONICS, INC. 16799 SCHOENBORN ST. NORTH HILLS, CA 91343 CSE610a Rev. - 10/24/96 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 Interface Module for Multiport Applications ELECTRONICS INC. EPE6104 The circuit below is a guideline for interconnecting PCA’s EPE6104 with NSC DP83950B Repeater/10 Base-T PHY chip over UTP cable. 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. Additionally, note that NSC suggests using a set of resistor networks with lower values suitable for more optimum voltage level control. Users can obtain modules with either values from PCA (EPE6092). But please check with NSC to find which set suits most for your specific application. EPE6104 has the lower values. Effective termination impedance offered by the outputs of the transmit channel is 2*(62//303)//800Ω or approximately 92Ω. Thus, bench testing of return loss needs to add approx. 7.5Ω on each leg of the transmit inputs to take into account the 74ACTXXXX output impedance. Note that some systems have auto polarity detection and some do not. If not, be certain to follow the proper polarity. It is recommended that system designers ground the chip side center taps via a low voltage capacitor. Taking the cable side center taps to chassis via capacitors, is not recommended, as this will add cost without containing EMI. This may worsen EMI, specifically if the primary “common mode termination” is pulled to ground as shown. The pull down resistors used 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 EPE6104. 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 one port only) TX+ 2 8 3 1 6 6 3 9 1 4 11 2 TXd+ DP83950B PHY TXTXdRX+ TX+ TX- RJ45 RX+ RX4 5 7 8 16 RX14 EPE6104 7 Chassis Ground Notes : * Pin-outs shown are for Hub/Repeater Applications only. PCA ELECTRONICS, INC. 16799 SCHOENBORN ST. NORTH HILLS, CA 91343 CSE6104b Rev. - 10/24/96 TEL: (818) 892-0761 FAX: (818) 894-5791 http://www.pca.com