MB86961A Datasheet, PDF (4/29 Pages) Fujitsu Component Limited. – UNIVERSAL INTERFACE FOR 10BASET

MB86961A
SIGNAL DESCRIPTIONS
Symbol
AUTOSEL
Type
I
CD
O
CIP
I
CIN
I
CLKO
O
CLKI
I
COL
O
DIP
I
DIN
I
DOP
O
DON
O
JAB
O
LBK
I
LEDC/XLBK
O/I
LEDL
O/I
LEDR
O
LEDT/
O/I
PDN
LI
I
MD0
I
MD1
I
NTH
I
PAUI
I
PLR
O
RBIAS
I
RCLK
O
Description
AUTOMATIC PORT SELECT: When AUTOSEL=1, automatic port selection is
enabled (The MB86981A defaults to the AUI port only if TP link integrity=Fail). When
AUTOSEL=0, manual port selection is enabled (the PAUI pin determines the active
port).
CARRIER DETECT: An output to notify the controller of activity on the network.
AUI COLLISION PAIR: Differential input pair connected to the AUI transceiver CI cir-
cuit. The input is collision signaling or SQE.
CRYSTAL OSCILLATOR: A 20MHz crystal must be connected across these pins, or
a 20 MHz clock applied at CLKI.
COLLISION DETECT: Output which drives the collision detect input of the controller.
AUI RECEIVE PAIR: Differential input pair from the AUI transceiver DI circuit. The
input is Manchester encoded.
AUI TRANSMIT PAIR: A differential output driver pair for the AUI transceiver cable.
The output is Manchester encoded.
JABBER INDICATION: Output goes high to indicate Jabber state.
LOOPBACK: When LBK=1, forced loopback is enabled. When LBK=0, normal loop-
back is enabled.
COLLISION LED: Open drain driver for the collision indicator. Output is pulled low
during collision ( half-duplex mode). If externally tied low, the MB86961A disables
the internal TP loopback and collision detection circuits in anticipation of external TP
loopback or full-duplex operation. MB86961A is ready for loopback testing 16 ms
after this pin goes low. No delay is needed when the pin goes high.
LINK LED: Open drain driver for link integrity indicator. Output pulled low during link
test pass. If externally tied low, internal circuitry is forced to “Link Pass’ state and the
MB86961A will continue to transmit link test pulses.
RECEIVE LED: Open drain driver for the receive indicator LED. Output is pulled low
during receive.
TRANSMIT LED/POWER DOWN: Open drain driver for the transmit indicator. Out-
put is pulled low during transmit. If externally tied low, the MB86961A goes to power
down state.
LINK TEST ENABLE: When LI=0, the Link Integrity Test function is disabled. When
LI=1, the Link Integrity Test function is enabled.
MODE SELECT: Mode select pins which determine controller compatibility mode.
See Table 1.
NORMAL THRESHOLD: When NTH=1, the normal TP squelch threshold is in
effect. When NTH=0, the normal TP squelch threshold is reduced by 4.5 dB.
PORT/AUI SELECT: In Manual Port Select mode (AUTOSEL=0), PAUI selects the
active port. When PAUI=1, the AUI port is selected, When PAUI=0, the TP port is
selected. In Auto Port Select mode, PAUI is ignored.
POLARITY REVERSE: Output goes high to indicate reversed polarity.
BIAS CONTROL: A bias resistor at this pin controls the bias of the operating circuit.
RECEIVE CLOCK: A recovered 10 MHz clock which is synchronous with the
received data and connected to the controller receive clock input.
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