ML6680 Datasheet, PDF (1/12 Pages) Micro Linear Corporation – Token Ring Copper-to-Fiber Converter

January 1997
ML6680
Token Ring Copper-to-Fiber Converter
GENERAL DESCRIPTION
The ML6680 is a single-chip conversion between Token
Ring ISO/IEC8802-5 copper-based media and Token Ring
ISO/IEC8802-5 fiber-based media. The ML6680 fiber-optic
interface contains a data quantizer, circuitry for fiber optic
key signal generation and recognition, pin-selectable
signal switching, and current driven transmitter outputs.
The ML6680 copper interface consists of a twisted pair
line equalizer, receive squelch circuit, pin selectable
phantom wire fault detection and signal switching, and a
transmit driver. This section supports the ISO/IEC8802-5
standard requirements. The ML6680 provides an optional
PECL compatible interface.
The ML6680 may be configured to one of four modes:
1. Standard Media Converter
2. Concentrator Media Converter
3. Lobe or Ring Out Port Media Converter
4. Ring In Port Media Converter
FEATURES
s Single-chip copper-to-fiber converter for Token Ring
s 16Mbps and 4Mbps data rates with the same
external components
s Four modes of operation covering a wide variety
of applications
s Full duplex operation
s Highly stable data quantizer with 55dB input
dynamic range
s Current driven fiber optic LED driver for accurate
launch power
s Current driven output for low RFI noise and low jitter
s Capable of driving 100Ω UTP or 150Ω STP
s Pin selectable phantom wire fault detection and
signal switching
BLOCK DIAGRAM
TPINP
TPINN
EQA
EQB
TWISTED PAIR
EQUALIZER
RTSETOP
LED
DRIVER
OPVCC
OPOUT
TPINOK
RTSETTP
TPOUTP
TPOUTN
PHTM1
PHTM2
TWISTED PAIR
RECEIVE SQUELCH
TWISTED PAIR
DRIVER
PHANTOM
DRIVER
SIGNAL
MUX
CONTROL
LOGIC
FIBER OPTIC
RECEIVE SQUELCH
OPINOK
FIBER OPTIC
QUANTIZER
BIAS
OPINP
OPINN
VDC
CRYSTAL
OSCILLATOR
XTAL1
XTAL2
KEYGEN INSERTED
1