78Q8392LA03-CP/F

78Q8392LA03-CP/F Datasheet

78Q8392L/A03 Low Power Ethernet Coaxial Transceiver

Part	Datasheet
78Q8392LA03-CP/F	78Q8392LA03-CP/F (pdf)

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78Q8392L/A03 Low Power Ethernet Coaxial Transceiver The 78Q8392L/A03 Ethernet Transceiver is a replacement for the SSI/TDK/Teridian 78Q8392L/A02 coax line transmitter/receiver. Only a single resistor value change is required for upgrading an existing 78Q8392L/A02 design to the 78Q8392L/A03. The device includes analog transmit and receive buffers, a 10 MHz on-board oscillator, timing logic for jabber and heartbeat functions, output drivers and bandgap reference, in addition to a current reference and collision detector. This transceiver provides the interface between the single-ended coaxial cable signals and the Manchester-encoded differential logic signals. Primary functional blocks include the receiver, transmitter, collision detection and jabber timer. This IC may be used in either internal or external MAU environments. The 78Q8392L/A03 is available in lead-free 16-pin plastic and 28-pin PLCC packages. November 2008 • Very low power consumption • Compliant with Ethernet II, IEEE 10Base5 and 10Base2 • Integrates all transceiver functions except signal and power isolation • Innovative design minimizes external component count and power consumption • Jabber timer function integrated on chip • Externally selectable CED heartbeat allows operation with IEEE compatible repeaters • Squelch circuitry at all inputs rejects noise • Power-on reset and test modes • Advanced BiCMOS process CONNECT DIAGRAM 510 ±5% x4 COLLISION SIGNAL TO DTE DATA TO DTE DATA FROM DTE 1 CD+ 3 RX+ 6 7 TX+ 78 8 TX- VEE 4 VEE 5 VEE 13 CDS 16 TXO 15 RXI 14 GND 10 HBE 9 12 RR- RR+ 11 COAX Page 1 of 14 2008 Teridian Semiconductor Corporation FUNCTIONAL DESCRIPTION The 78Q8392L/A03 incorporates six basic functions of the Ethernet Transceiver, including receiving, transmitting, collision signaling, collision detection, jabber timing, and the heartbeat function. Refer to Figure 1 for a general system block diagram. RECEIVER FUNCTIONS The receiver senses signals through the RXI input, which minimizes reflections on the transmission media using a low capacitance, high resistance input buffer amplifier. The CDS ground input attaches directly to the input buffer from the coaxial shield to eliminate ground loop noise. In addition to the input buffer, the receiver data path consists of an equalizer, data slicer, receiver squelch circuitry, and an output line driver. The equalizer improves the cable-induced jitter the data slicer restores equalized received signals to fast transition signals with binary levels to drive the receiver line driver and the receiver line driver drives the AUI cable through an isolation transformer that connects to the AUI interface. Noise on the transmission media is rejected by the receiver squelch circuitry, which determines valid data via three criteria Average DC level, pulse width and transition period. The DC voltage level is detected and compared to a set level in the receiver comparator circuit. The pulse width must be greater than 20 ns to pass the narrow pulse filter the transition timer outputs a true level on the RX Data Valid line provided the time between transitions is less than about 200 ns. As long as a valid RXI signal is detected, the output line driver remains enabled. The transition timer disables the line driver when there are no further transitions on the data medium, and the RX+, RX- pins go to a zero differential voltage state Figure TRANSMITTER FUNCTIONS The transmitter data path consists of a transmit input buffer, pulse-shaping filter, transmit squelch circuitry and transmit output line driver. The self-biasing transmit input buffer receives data through an isolation transformer and translates the AUI differential analog signal to a square pulse suitable for driving the pulse shaping filter. 78Q8392L/A03 Low Power Ethernet Coaxial Transceiver The filter outputs a correctly shaped and band limited signal to the transmit output driver, which drives the transmission medium through a high impedance current source. When the transmitter is off, the capacitance of the transmit driver is isolated from the transmission media by an external diode with a low capacitance node. The shield of the transmission media serves as the ground return for the transmitter function. A transmit squelch circuit, which consists of a pulse threshold detector, a pulse width detector, and a pulse duration timer, is used to suppress noise, as well as crosstalk on the AUI cable. The squelch circuitry disables the transmit driver if the signal at TX+ or TX- is smaller than the pulse threshold. Pulse noise is rejected by a pulse width detector that passes only pulses with durations greater than 20 ns. The pulse duration timer disables the transmit driver if no pulses are received for two-bit periods following valid pulses. At the end of a transmission, the pulse duration timer disables the transmitter and triggers the blanking timer, used to block “dribble” bits. COLLISION DETECTION A collision occurs when two or more transmitters simultaneously transmit on the transmission media. A collision is detected by comparing the average DC level of the transmission media to a collision threshold. The received signal at RXI is buffered and sent through a low pass filter, then compared in the collision threshold circuit. If the average DC level exceeds a collision threshold, a 10 MHz signal is output on the CD± pins. COLLISION SIGNALING ORDERING INFORMATION PART DESCRIPTION 78Q8392L/A03 16-Pin Plastic DIP lead free 78Q8392L/A03 28-Pin Plastic PLCC lead free 78Q8392L/A03 Low Power Ethernet Coaxial Transceiver ORDER NUMBER 78Q8392LA03-CP/F 78Q8392LA03-28CH/F PACKAGE MARK 78Q8392L-CP SP Date Code P3F Lot Number 78Q8392L-28CH SP Date Code P3F Lot Number Date December 2005 January 2006 November, 2008 Comments Final Data Sheet release Corrected package marking error from C to P Added package dimensions This product is sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement and limitation of liability. Teridian Semiconductor Corporation TSC reserves the right to make changes in specifications at any time without notice. Accordingly, the reader is cautioned to verify that the data sheet is current before placing orders. TSC assumes no liability for applications assistance. Teridian Semiconductor Corp., 6440 Oak Canyon Suite 100, Irvine, CA 92618 TEL 714 508-8800, FAX 714 508-8877, Page 14 of 14 2008 Teridian Semiconductor Corporation

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78Q8392L/A03 Low Power Ethernet Coaxial Transceiver

The 78Q8392L/A03 Ethernet Transceiver is a replacement for the SSI/TDK/Teridian 78Q8392L/A02 coax line transmitter/receiver. Only a single resistor value change is required for upgrading an existing 78Q8392L/A02 design to the 78Q8392L/A03.

The device includes analog transmit and receive buffers, a 10 MHz on-board oscillator, timing logic for jabber and heartbeat functions, output drivers and bandgap reference, in addition to a current reference and collision detector.

This transceiver provides the interface between the single-ended coaxial cable signals and the Manchester-encoded differential logic signals. Primary functional blocks include the receiver, transmitter, collision detection and jabber timer. This IC may be used in either internal or external MAU environments.

The 78Q8392L/A03 is available in lead-free 16-pin plastic and 28-pin PLCC packages.

November 2008
• Very low power consumption
• Compliant with Ethernet II, IEEE
10Base5 and 10Base2
• Integrates all transceiver functions except
signal and power isolation
• Innovative design minimizes external
component count and power consumption
• Jabber timer function integrated on chip
• Externally selectable CED heartbeat allows
operation with IEEE compatible repeaters
• Squelch circuitry at all inputs rejects noise
• Power-on reset and test modes
• Advanced BiCMOS process

CONNECT DIAGRAM
510 ±5% x4

COLLISION SIGNAL TO DTE

DATA TO DTE

DATA FROM DTE
1 CD+
3 RX+
6 7 TX+ 78 8 TX-

VEE 4 VEE 5 VEE 13 CDS 16 TXO 15 RXI 14 GND 10

HBE 9
12 RR-

RR+ 11

COAX

Page 1 of 14
2008 Teridian Semiconductor Corporation

FUNCTIONAL DESCRIPTION

The 78Q8392L/A03 incorporates six basic functions of the Ethernet Transceiver, including receiving, transmitting, collision signaling, collision detection, jabber timing, and the heartbeat function. Refer to Figure 1 for a general system block diagram.

RECEIVER FUNCTIONS

The receiver senses signals through the RXI input, which minimizes reflections on the transmission media using a low capacitance, high resistance input buffer amplifier. The CDS ground input attaches directly to the input buffer from the coaxial shield to eliminate ground loop noise.

In addition to the input buffer, the receiver data path consists of an equalizer, data slicer, receiver squelch circuitry, and an output line driver.

The equalizer improves the cable-induced jitter the data slicer restores equalized received signals to fast transition signals with binary levels to drive the receiver line driver and the receiver line driver drives the AUI cable through an isolation transformer that connects to the AUI interface.

Noise on the transmission media is rejected by the receiver squelch circuitry, which determines valid data via three criteria Average DC level, pulse width and transition period. The DC voltage level is detected and compared to a set level in the receiver comparator circuit. The pulse width must be greater than 20 ns to pass the narrow pulse filter the transition timer outputs a true level on the RX Data Valid line provided the time between transitions is less than about 200 ns. As long as a valid RXI signal is detected, the output line driver remains enabled. The transition timer disables the line driver when there are no further transitions on the data medium, and the RX+, RX- pins go to a zero differential voltage state Figure

TRANSMITTER FUNCTIONS

The transmitter data path consists of a transmit input buffer, pulse-shaping filter, transmit squelch circuitry and transmit output line driver. The self-biasing transmit input buffer receives data through an isolation transformer and translates the AUI differential analog signal to a square pulse suitable for driving the pulse shaping filter.
78Q8392L/A03 Low Power Ethernet Coaxial Transceiver

The filter outputs a correctly shaped and band limited signal to the transmit output driver, which drives the transmission medium through a high impedance current source. When the transmitter is off, the capacitance of the transmit driver is isolated from the transmission media by an external diode with a low capacitance node. The shield of the transmission media serves as the ground return for the transmitter function.

A transmit squelch circuit, which consists of a pulse threshold detector, a pulse width detector, and a pulse duration timer, is used to suppress noise, as well as crosstalk on the AUI cable. The squelch circuitry disables the transmit driver if the signal at TX+ or TX- is smaller than the pulse threshold. Pulse noise is rejected by a pulse width detector that passes only pulses with durations greater than 20 ns. The pulse duration timer disables the transmit driver if no pulses are received for two-bit periods following valid pulses. At the end of a transmission, the pulse duration timer disables the transmitter and triggers the blanking timer, used to block “dribble” bits.

COLLISION DETECTION

A collision occurs when two or more transmitters simultaneously transmit on the transmission media. A collision is detected by comparing the average DC level of the transmission media to a collision threshold. The received signal at RXI is buffered and sent through a low pass filter, then compared in the collision threshold circuit. If the average DC level exceeds a collision threshold, a 10 MHz signal is output on the CD± pins.

COLLISION SIGNALING
ORDERING INFORMATION

PART DESCRIPTION 78Q8392L/A03 16-Pin Plastic DIP lead free
78Q8392L/A03 28-Pin Plastic PLCC lead free
78Q8392L/A03 Low Power Ethernet Coaxial Transceiver

ORDER NUMBER 78Q8392LA03-CP/F 78Q8392LA03-28CH/F

PACKAGE MARK
78Q8392L-CP

SP Date Code P3F Lot Number
78Q8392L-28CH

SP Date Code P3F Lot Number

Date December 2005 January 2006 November, 2008

Comments Final Data Sheet release Corrected package marking error from C to P Added package dimensions

This product is sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement and limitation of liability. Teridian Semiconductor Corporation TSC reserves the right to make changes in specifications at any time without notice. Accordingly, the reader is cautioned to verify that the data sheet is current before placing orders. TSC assumes no liability for applications assistance.

Teridian Semiconductor Corp., 6440 Oak Canyon Suite 100, Irvine, CA 92618 TEL 714 508-8800, FAX 714 508-8877,

Page 14 of 14
2008 Teridian Semiconductor Corporation

Notice: we do not provide any warranties that information, datasheets, application notes, circuit diagrams, or software stored on this website are up-to-date or error free. The archived 78Q8392LA03-CP/F Datasheet file may be downloaded here without warranties.

Datasheet ID: 78Q8392LA03-CP/F 647142