Philips Semiconductors
Product specification
Coaxial transceiver interface for Ethernet/Thin Ethernet
DESCRIPTION
NE8392C
PIN CONFIGURATION
The NE8392C Coaxial Transceiver Interface (CTI) is a bipolar
coaxial line driver/receiver for Ethernet (10base5) and Thin Ethernet
(10base2) local area networks. The CTI is connected between the
coaxial cable and the Data Terminal Equipment (DTE) and consists
of a receiver, transmitter, receive-mode collision detector, heartbeat
generator and jabber timer (see Block Diagram). The transmitter
output connects directly to a doubly terminated 50Ω cable, while the
receiver output, collision detector output and transmitter input are
connected to the DTE through isolation transformers. Isolation
between the CTI and the DTE is an IEEE 802.3 requirement that
can be met on signal lines by using a set of pulse transformers
normally available in a standard 16-pin DIP. Power isolation for the
CTI is achieved using DC-to-DC conversion through a power
transformer (see Figure 1, Connection Diagram).
N PACKAGE
16 CDS
CD+
1
CD–
2
15 TXO
3
14
VEE
4
13 VEE
VEE
5
12 RR–
RX–
6
11 RR+
TX+
7
10 GND
TX–
8
RX+
During transmission the jabber timer is initiated to disable the CTI
transmitter in the event of a longer than legal length data packet.
Receive-mode collision detection circuitry monitors the signals on
the coaxial cable to determine the presence of colliding packets and
signals the DTE in the event of a collision. At the end of every
transmission the heartbeat generator creates a pseudo collision for
a short time to ensure that the collision circuitry is functioning
correctly. The heartbeat function can be disabled for repeater
applications.
9
RXI
HBE
2
1
RXI
CDS
3
N/C
CD+
4
TXO
RX+
CD–
A PACKAGE
28 27 26
V
EE 5
V
EE 6
V
EE 7
V
EE 8
V
EE 9
V
EE 10
V
EE 11
24
23
22
21
20
19
RR+
GND
HBE
• Compatible with Ethernet II IEEE 802.3 10base5 and 10base2,
V
EE
V
EE
V
EE
V
EE
V
EE
V
EE
RR–
14 15 16 17 18
GND
RX–
FEATURES
TX+
12 13
TX–
The CTI is normally part of a three chip set that implements a
complete Ethernet/ Thin Ethernet network interface for a DTE (see
Figure 2, Interface Diagram). The other chips are a Serial Network
Interface (SNI) and a Network Interface Controller (NIC). The SNI
provides Manchester Encoding and Decoding while the NIC handles
the media access protocol and buffer management tasks.
25
SD00283
and ISO 8802/3 interface specifications
• 100% drop-in compatible with industry standard 8392 sockets
• Integrates all transceiver electronics except signal and power
• On-chip precision voltage reference for receive mode collision
detection
• Squelch circuitry on all signal inputs rejects noise
• Full ESD protection
• Standard 16-pin DIP and 28-pin PLCC packages
• Power-on reset prevents glitches on coaxial cable during power
isolation
• Only one external resistor required for setting coaxial signaling
current
• Jabber timer function integrated on chip
• Heartbeat generator can be externally disabled for operation as
up.
IEEE 802.3 compatible repeaters
• Also available in advanced low-power BiCMOS technology. (See
selection chart and data sheets for the NE83C92, NE83Q92 or
NE83Q93 for appropriate optimal usages)
ORDERING INFORMATION
TEMPERATURE RANGE
ORDER CODE
DWG #
16-Pin Plastic Dual In-Line Package (DIP)
DESCRIPTION
0 to +70°C
NE8392CN
SOT28-4
28-Pin Plastic Lead Chip Carrier (PLCC)
0 to +70°C
NE8392CA
SOT261-3
1995 May 1
1
853-1693 15180