LAN88710AM SMSC, LAN88710AM Datasheet - Page 45

• Manufacturer Part Number: LAN88710AM
• Description: Ethernet ICs MII/RMII 10/100 Automot Transceiver
• Manufacturer: SMSC

Specifications of LAN88710AM

• Ethernet Connection Type: 10BASE-T, 100BASE-TX
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Product: Ethernet Transceivers
• Standard Supported: IEEE802.3, IEEE802.3u
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 1.6 V
• Maximum Operating Temperature: + 85 C
• Package / Case: QFN-32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Small Footprint MII/RMII 10/100 Ethernet Transceiver for Automotive Applications
Datasheet
SMSC LAN88710AM/LAN88710BM
3.8.9
3.8.9.1
3.8.9.2
Ethernet
10/100
MAC
Ethernet
10/100
MAC
Loopback Operation
The device may be configured for near-end loopback and far loopback. These loopback modes are
detailed in the following subsections.
Near-end Loopback
Near-end loopback mode sends the digital transmit data back out the receive data signals for testing
purposes, as indicated by the blue arrows in
setting the
is operational in near-end loopback mode because data is routed through the PCS and PMA layers
into the PMD sublayer before it is looped back. The COL signal will be inactive in this mode, unless
Collision Test
of the state of TXEN.
Far Loopback
This special test mode is only available when operating in RMII mode. When the RMIISEL
configuration strap is configured for MII mode, the SMI can be used to override this setting as
described in
Far loopback is a special test mode for MDI (analog) loopback as indicated by the blue arrows in
Figure
Control/Status Register
looped back out to the link partner. The digital interface signals on the local MAC interface are isolated.
TXD
3.8. The far loopback mode is enabled by setting the
RXD
Loopback
TXD
Section
X
X
is enabled in the
RXD
Digital
Ethernet Transceiver
Figure 3.7 Near-end Loopback Block Diagram
3.7.3.
Far-end system
bit of the
Digital
Figure 3.8 Far Loopback Block Diagram
Ethernet Transceiver
to “1”. In this mode, data that is received from the link partner on the MDI is
SMSC
SMSC
Basic Control Register
Basic Control
Analog
DATASHEET
Analog
45
Register. The transmitters are powered down regardless
Figure
TX
RX
X
X
3.7. The near-end loopback mode is enabled by
to “1”. A large percentage of the digital circuitry
TX
RX
XFMR
XFMR
FARLOOPBACK
CAT-5
Revision 1.1 (05-26-10)
CAT-5
bit of the
Partner
Link
Mode