March 1997

ML4667

Low Power 10BASE-FL Transceiver

GENERAL DESCRIPTION

The ML4667 is a low power high output current pin

compatible version of the industry standard ML4662. The

ML4667 10Base-FL transceiver combined with either the

ML4622 or ML4624 fiber optic quantizer provide all

functionality required to implement both an internal and

external IEEE 802.3 10Base-FL MAU interface that allows

it to be directly connected to industry standard

manchester encoder/decoder chips or and AUI cable.

The ML4667 provides a highly integrated solution that

requires a minimal number of external components. The

ML4667 is compliant to the IEEE 802.3 10Base-FL

standard. The transmitter offers a 100mA maximum

current driven output that directly drives a fiber optic LED

transmitter. Jabber, a 1MHz idle signal, and SQE Test are

fully integrated onto the chip.

The receiver accepts and ECL level input from the

ML4622 or ML4624 fiber optic quantizer. The 1MHz idle

signal is removed and the AUI output is activated when

the receive squelch criteria is exceeded. A Link Monitor

function is also provided for low light detection.

FEATURES

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Combined with the ML4622 or ML4624, offers a

complete implementation of an 10Base-FL Medium

Attachment Unit (MAU)

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Pin compatible with the ML4662 Transceiver

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Incorporates an AU interface for use in an external

MAU or an internal MAU

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100mA max LED output current drive

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Single +5 volt supply

±10%

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No crystal or clock required

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On-chip Jabber, 1MHz idle, and SQE Test with enable/

disable option

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Five network status LED outputs

BLOCK DIAGRAM

1

RECEIVE SQUELCH

FREQUENCY

LINE

RECEIVER

LED

DRIVERS

LOOPBACK

MUX

AUI

DRIVER

AUI

DRIVER

10MHz GATED

OSCILLATOR

SQE

1MHz

IDLE

SIGNAL

Tx

SQUELCH

AUI

RECEIVER

FIBER OPTIC

LED DRIVER

JABBER

SQEN/JABD

(+5V)

+5V

RTSET

NC/PEAK

TxOUT

RxIN+

RxIN–

BIAS

LMON

XMT

RCV

JAB

CLSN

LBDIS

RRSET

+5V

(+5V)

GND

Rx–

Rx+

COL–

COL+

Tx–

Tx+

Tx

Rx

10

11

2

3

6

7

21

8

13

23

1

28

16

15

24

27

25

26

22

18

19

17

4

12