MYSON

TECHNOLOGY

MTD492

Coaxial Transceiver Interface

This datasheet contains new product information. Myson Technology reserves the rights to modify the product specification without notice. No

liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product.

MTD492 Revision 3.5 01/07/1997

1/8

FEATURES

•

Compatible with IEEE 802.3 10Base5 (Ethernet) and 10Base2 (Cheapernet).

•

Internal AUI squelch circuitry for noise rejection.

•

Transmission IDL detection at end of packet and dribble bit rejection window.

•

Reception dribble bit rejection window.

•

Reception and transmission mode collision detection.

•

Extended collision detection to turn off receiving path.

•

CD heartbeat externally controllable.

•

Advanced low-power, high-performance CMOS technology.

•

ESD protection greater than 2000 Volts.

•

16-pin PDIP and 28-pin PLCC packages.

GENERAL DESCRIPTION

The MTD492 transceiver integrates the coaxial cable interface functions of the Medium Attachment Unit

(MAU) in Ethernet or Cheapernet LAN applications. In an Ethernet 10Base5 network, MTD492 is mounted

on the thick Ethernet coaxial cable and connects to a station through an AUI cable. For Cheapernet

applications, MTD492 is connected to the Cheapernet coaxial cable through a BNC connector and is

usually mounted on the LAN adapter in a station.

BLOCK DIAGRAM

HIGH PASS

EQUALIZATION

LOW PASS

FILTER

LOW PASS

FILTER

COM

-

+

LOW PASS

FILTER

125

10K

REFERENCE

CIRCUIT

1K

AUI

DRIVER

AUI

DRIVER

CARRIER

SENSE

-

+

WAVEFORM

SHAPING

+

-

DC/AC

SQUELCH

WATCH DOG

TIMER 26ms

JABBER RESET

TIMER 0.4sec

10MHz

OSC

TRANSMIT

STATE

MACHINE

RECEIVE

STATE

MACHINE

XMTSQ

CLK

VEE

COLLISION

HBE

FXI

GND

COAX

VEE

XMT

CDS

RECV

TXO

RR+

RR-

RX+

RX-

CD+

CD-

TX+

TX-