78Q2123/F Maxim Integrated Products, 78Q2123/F Datasheet - Page 18

• Manufacturer Part Number: 78Q2123/F
• Description: TXRX 10/100 MDIX 3.3V COMM 32QFN
• Manufacturer: Maxim Integrated Products
• Type: 10/100 Fast Ethernetr

Specifications of 78Q2123/F

• Operating Supply Voltage: 3.3 V
• Supply Current: 88 mA
• Operating Temperature Range: 0 to + 70 C
• Package / Case: QFN-32
• Mounting Style: SMD/SMT
• Operating Frequency: 25 MHz
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

78Q2123/78Q2133 Data Sheet
Note: Technology Ability Field: MR4.12:5 are the Technology Ability Field bits (A7:0). The default value
of this field is dependent upon the MR1.15:11 register bits. This field can be overwritten by management
to auto-negotiate to an alternate common technology. Writing to this register has no effect until
auto-negotiation is re-initiated.
3.6
3.7
3.8
18
5.12:5
6.15:5
16.15
4.4:0
5.4:0
5.15
5.14
5.13
4.5
Bit
Bit
6.4
6.3
6.2
6.1
6.0
Bit
MR5: Auto-Negotiation Link Partner Ability Register
MR6: Auto-Negotiation Expansion Register
MR16: Vendor Specific Register
LPANEGA
Symbol
Symbol
Symbol
LPNPA
RPTR
RSVD
S4:0
ACK
A7:0
S4:0
PDF
NPA
PRX
NP
RF
A0
Type
Type
R/W
Type
R/W
RC
RC
R
R
R
R
R
R
R
R
R
R
Default
Default
Default
01h
00h
(1)
0
0
0
0
0
0
0
0
0
0
(0)
10BASE-T: If the MR1.11 bit is ‘1’, this bit will be set to ‘1’
upon reset and will be writeable. Otherwise, this bit cannot be
set to ‘1’ by the management.
Selector Field: Hard coded with the value of ‘00001’ for IEEE
802.3.
Description
Next Page: When ‘1’ is read, it indicates the link partner
wishes to engage in Next Page exchange.
Acknowledge: When ‘1’ is read, it indicates the link partner has
successfully received at least 3 consecutive and consistent
FLP bursts.
Remote Fault: When ‘1’ is read, it indicates the link partner has
a fault.
Technology Ability Field: This field contains the technology
ability of the link partner. The bit definition is the same as
MR4.12:5.
Selector Field: This field contains the type of message sent by
the link partner. For an IEEE 802.3 compliant link partner, this
field should be ‘00001’.
Description
Reserved
Parallel Detection Fault: When ‘1’ is read, it indicates that
more than one technology has been detected during link up.
This bit is cleared when read.
Link Partner Next Page Able: When ‘1’ is read, it indicates the
link partner supports the Next Page function.
Next Page Able: Reads ‘0’ since the 78Q2123/78Q2133 do not
support Next Page function.
Page Received: Reads ‘1’ when a new link code word has
been received into the Auto-Negotiation Link Partner Ability
Register. This bit is cleared upon read.
Link Partner Auto-Negotiation Able: When ‘1’ is read, it
indicates the link partner is able to participate in the Auto-
Negotiation function.
Description
Repeater Mode: When set, the 78Q2123/78Q2133 are put
into Repeater mode of operation. In this mode, full duplex is
DS_21x3_001
Rev. 1.6