KSZ8721SL A4 Micrel Inc, KSZ8721SL A4 Datasheet - Page 8
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KSZ8721SL A4
Manufacturer Part Number
KSZ8721SL A4
Description
Manufacturer
Micrel Inc
Datasheet
1.KSZ8721SL_A4.pdf
(34 pages)
Specifications of KSZ8721SL A4
Lead Free Status / RoHS Status
Compliant
KS8721BL/SL
10BASE-T.
T.
T.
tion
Notes:
1. P = Power supply.
M9999-022105
Pin Number
GND = Ground.
I = Input.
I/O = Bidirectional.
Ipd = Input w/ internal pull-down.
Ipd/O = Input w/ internal pull-down during reset, output pin otherwise.
Ipu = Input w/ internal pull-up.
Ipu/O = Input w/ internal pull-up during reset, output pin otherwise.
O = Output.
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
FXSD/FXEN
Pin Name
VDDRCV
VDDPLL
VDDRX
VDDTX
REXT
RST#
GND
GND
GND
GND
GND
RX+
TX+
RX-
TX-
XO
XI
Type
Ipd/O
GND
GND
GND
GND
GND
Ipu
P
P
O
O
P
O
P
I
I
I
I
(1)
Pin Function
Analog 2.5V power supply. See “Circuit Design Ref. for Power Supply” section for
details.
Receive Input. Differential receive input pins for 100FX, 100BASE-TX, or
Receive Input: Differential receive input pin for 100FX, 100BASE-TX, or 10BASE-
Fiber Mode Enable / Signal Detect in Fiber Mode. If FXEN = 0, FX mode is
disable. The default is “0”. See “100BT FX Mode” section for more details.
Ground.
Ground.
External resistor (6.49kW ) connects to REXT and GND.
Analog 2.5V power supply. 2.5V power output of voltage regulator. See “Circuit
Design Ref. for Power Supply” section for details.
Ground.
Transmit Outputs: Differential transmit output for 100FX, 100BASE-TX, or
10BASE-T.
Transmit Outputs: Differential transmit output for 100FX, 100BASE-TX, or 10BASE-
Transmitter 2.5V power supply. See “Circuit Design Ref. for Power Supply” sec-
Ground.
Ground.
XTAL feedback: Used with XI for Xtal application.
Crystal Oscillator Input: Input for a crystal or an external 25MHz clock.
If an oscillator is used, XI connects to a 3.3V tolerant oscillator, and X2 is a no-
connect.
Analog PLL 2.5V power supply. See “Circuit Design Ref. for Power Supply”
section for details.
Chip Reset. Active low, minimum of 50µs pulse is required.
for details.
8
February 2005
Micrel