Proper Connection for Twisted Pair
Each twisted pair compatible ARCNET node would typically have two RJ-11 modular connectors mounted on the
node card (refer to Figure 4). PHASE A should be connected to pin 2 of the connectors and PHASE B to pin 3. A
twisted pair segment would have an RJ-11 modular jack on each end (see Figure 5). Please note that the suggested
numbering scheme of the modular jack shown in Figure 5 may not be consistent with that found on some manufacturers'
products. Please ensure consistent connection of Phase A and Phase B signals throughout the network to avoid the
reception of erroneous data.
Table 1 - Specifications for Cabling
VALUE FOR COAX
VALUE FOR TWISTED PAIR
RG62
N/A
3.4 Ohms/1000 ft.
93 Ohms at 1 MHz
5.5 dB/1000 ft. at 5 MHz
Solid Copper 22, 24, or 26 AWG
2 min.
28.6 Ohms/1000 ft. max.
105 Ohms
20% at 1 MHz
16.0 dB/1000 ft. at 5 MHz
PARAMETER
Wiring
Number of Twists/Foot
DC Resistance
Characteristic Impedance
Maximum Attenuation
DISABLE
19
ISOLATION
TRANSFORMER
nPULSE 1
20
FILTER,
AMPLIFIER
AND
DIFFERENTIAL
DRIVER
1
2
NC
NC
5
9
NC
NC
12
PH-A/CENTER
nPULSE 2
18
11
PH-B/SHIELD
8
Rx
DATA
7
VOLTAGE
THRESHOLD
DETECTOR
FILTER
TPA
TPB
TPC
TPD
16
15
10
6
4
3
13
14
17
+5V GND -5V
GND GND GND
FIGURE 1 – HYC9088A INTERNAL BLOCK DIAGRAM
Revision (02-16-07)
Page 6
SMSC HYC9088A
DATASHEET
SMSC [ SMSC CORPORATION ]
