LAN9353 Datasheet, PDF (119/523 Pages) Microchip Technology – Interfaces at up to 200Mbps via Turbo MII

LAN9353
If Loss of Signal mode is not selected, then Signal Detect mode is selected, independently, by the FXSDENA or FXS-
DENB strap input pin. When greater than 1 V (typ.), Signal Detect mode is enabled, when less than 1 V (typ.), copper
twisted pair is enabled.
Note:
The FXSDENA strap input pin is shared with the FXSDA pin and the FXSDENB strap input pin is shared
with the FXSDB pin. As such, the LVPECL levels ensure that the input is greater than 1 V (typ.) and that
Signal Detect mode is selected. When TP copper is desired, the Signal Detect input function is not required
and the pin should be set to 0 V.
Care must be taken such that an non-powered or disabled transceiver does not load the Signal Detect input
below the valid LVPECL level.
Table 9-10 and Table 9-11 summarize the selections.
TABLE 9-10: 100BASE-FX LOS, SD AND TP COPPER SELECTION PHY A
FXLOSEN
<1 V (typ.)
>1 V (typ.)
FXSDENA
<1 V (typ.)
>1 V (typ.)
n/a
PHY Mode
TP copper
100BASE-FX Signal Detect
100BASE-FX LOS
TABLE 9-11: 100BASE-FX LOS, SD AND TP COPPER SELECTION PHY B
FXLOSEN
<1 V (typ.)
>2 V (typ.)
FXSDENB
<1 V (typ.)
>1 V (typ.)
n/a
PHY Mode
TP copper
100BASE-FX Signal Detect
100BASE-FX LOS
9.2.18 REQUIRED ETHERNET MAGNETICS (100BASE-TX AND 10BASE-T)
The magnetics selected for use with the device should be an Auto-MDIX style magnetic, which is widely available from
several vendors. Please review the SMSC/Microchip Application note 8.13 “Suggested Magnetics” for the latest quali-
fied and suggested magnetics. A list of vendors and part numbers are provided within the application note.
9.2.19 EXTERNAL PIN ACCESS TIMING REQUIREMENTS
When accessed externally via the MDIO / MDC pins, the following timing applies.
 2015 Microchip Technology Inc.
DS00001925A-page 119