78Q8392L-28CH ETC [List of Unclassifed Manufacturers], 78Q8392L-28CH Datasheet - Page 4

• Manufacturer Part Number: 78Q8392L-28CH
• Description: Low Power Ethernet Coaxial Transceiver
• Manufacturer: ETC [List of Unclassifed Manufacturers]

78Q8392L
Low Power Ethernet
Coaxial Transceiver
PIN DESCRIPTION
NAME
CD+*/CD-
RX+*/RX-
TX+*/TX-
HBE
RR+/RR-
RXI
TXO
CDS
GND
VEE
*IEEE names for CD± = CI±, RX± = DI±, TX± = DO±
Notes: Pin type: I-input; O-output; S-power supply
TYPE
O
O
O
S
S
I
I
I
I
I
DESCRIPTION
Collision Output. Balanced differential line driver outputs from the collision detect
circuitry. The 10 MHz signal from the internal oscillator is transferred to these outputs
in the event of collision, excessive transmission (jabber), or during CD Heartbeat
condition. These outputs are open emitters; pulldown resistors to VEE are required.
When operating into a 78
Cheapernet applications, where the 78
values (up to 1.5k) may be used to save power.
Receive Output. Balanced differential line driver outputs from the Receiver. These
outputs also require 510 pulldown resistors.
Transmit Input. Balanced differential line receiver inputs to the Transmitter. The
common mode voltage for these inputs is determined internally and must not be
externally established. Signals meeting Transmitter squelch requirements are
waveshaped and output at TXO.
Heartbeat Enable. This input enables CD Heartbeat when grounded or left opened,
disables it when connected to VEE.
External Resistor. A fixed 1 k
establishes internal operating currents.
Receive Input. Connects directly to the coaxial cable. Signals meeting Receiver
squelch requirements are equalized for inter-symbol distortion, amplified, and output
at RX+ and RX- pin.
Transmit Output. Connects via an isolation diode to the coaxial cable.
Collision Detect Sense. Ground sense connection for the collision detect circuit. This
pin should be connected separately to the shield to avoid ground drops from altering
the receive mode collision threshold.
Positive Supply Pin.
Negative Supply Pins. These pins should be connected to a large metal frame area
on the PC board to handle heat dissipation, and bypassed to the GND pin with a 0.1
F capacitor as close to the package as possible.
4
transmission line, these resistors should be 510 . In
1% resistor connected between these pins
drop cable is not used, higher resistor