LAN8720AI-CP-TR SMSC, LAN8720AI-CP-TR Datasheet - Page 32

• Manufacturer Part Number: LAN8720AI-CP-TR
• Description: Ethernet ICs 10/100 Ethernet XCVR w/HP AutoMDIXSupport
• Manufacturer: SMSC

Specifications of LAN8720AI-CP-TR

• Product: Ethernet Transceivers
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Revision 1.2 (11-10-10)
3.7.3
MODE[2:0]
000
001
010
100
101
011
110
111
The MODE[2:0] hardware configuration pins are multiplexed with other signals as shown in
REGOFF: Internal +1.2V Regulator Configuration
The incorporation of flexPWR technology provides the ability to disable the internal +1.2V regulator.
When the regulator is disabled, an external +1.2V must be supplied to the VDDCR pin. Disabling the
internal +1.2V regulator makes it possible to reduce total system power, since an external switching
regulator with greater efficiency (versus the internal linear regulator) can be used to provide +1.2V to
the transceiver circuitry.
Note: Because the REGOFF configuration strap shares functionality with the LED1 pin, proper
10Base-T Half Duplex. Auto-negotiation disabled.
10Base-T Full Duplex. Auto-negotiation disabled.
100Base-TX Half Duplex. Auto-negotiation
disabled.
CRS is active during Transmit & Receive.
100Base-TX Full Duplex. Auto-negotiation disabled.
CRS is active during Receive.
100Base-TX Half Duplex is advertised. Auto-
negotiation enabled.
CRS is active during Transmit & Receive.
Repeater mode. Auto-negotiation enabled.
100Base-TX Half Duplex is advertised.
CRS is active during Receive.
Power Down mode. In this mode the transceiver will
wake-up in Power-Down mode. The transceiver
cannot be used when the MODE[2:0] bits are set to
this mode. To exit this mode, the MODE bits in
Register 18.7:5(see
Register," on page
other value and a soft reset must be issued.
All capable. Auto-negotiation enabled.
consideration must also be given to the LED polarity. Refer to
LED1 Polarity Selection," on page 37
REGOFF and the LED1 polarity.
MODE DEFINITIONS
57) must be configured to some
Section 4.2.9, "Special Modes
MODE BIT
Table 3.5 Pin Names for Mode Bits
MODE[0]
MODE[1]
MODE[2]
Table 3.4 MODE[2:0] Bus
DATASHEET
32
CRS_DV/MODE2
RXD0/MODE0
RXD1/MODE1
PIN NAME
for additional information on the relation between
Small Footprint RMII 10/100 Ethernet Transceiver with HP Auto-MDIX Support
DEFAULT REGISTER BIT VALUES
REGISTER 0
[13,12,10,8]
X10X
0000
0001
1000
1001
1100
1100
N/A
Section 3.8.1.1, "REGOFF and
SMSC LAN8720A/LAN8720Ai
REGISTER 4
[8,7,6,5]
0100
0100
1111
N/A
N/A
N/A
N/A
N/A
Table
Datasheet
3.5.