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KSZ8081MLX

Physical Layer Transceiver

The KSZ8081MLX is a physical layer transceiver from Microchip Technology. View the full KSZ8081MLX datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

Manufacturer

Microchip Technology

Category

Physical Layer Transceiver

Package

48-pin LQFP

Key Specifications

ParameterValue
Data Rates10 Mbps, 100 Mbps
ESD Rating (HBM)6 kV
MDIO Clock Speedup to 10 MHz
Ethernet Standard10BASE-T/100BASE-TX IEEE 802.3
Package Dimensions7 mm x 7 mm (for 48-pin LQFP)
Core Supply Voltage1.2V (internal regulator)
Main Supply Voltage3.3V
Communication InterfacesMII, MDC/MDIO
Reference Clock Frequency25 MHz
I/O Supply Voltage Options1.8V, 2.5V, 3.3V

Overview

Part: KSZ8081MLX — Microchip

Type: 10BASE-T/100BASE-TX Ethernet Physical Layer Transceiver

Description: Single-supply 10BASE-T/100BASE-TX Ethernet physical-layer transceiver for data transmission and reception over CAT-5 UTP cable, featuring MII interface, integrated 1.2V core regulator, and 1.8V/2.5V/3.3V digital I/O support.

Operating Conditions:

  • Supply voltage: 3.3V (core), 1.8V/2.5V/3.3V (digital I/O)
  • Crystal/Oscillator/External Clock Input: 25 MHz ±50 ppm
  • Data rates: 10/100 Mbps

Key Specs:

  • HBM ESD Rating: 6 kV

Features:

  • Single-Chip 10BASE-T/100BASE-TX IEEE 802.3 Compliant Ethernet Transceiver
  • MII Interface Support
  • MDC/MDIO Management Interface for PHY Register Configuration
  • Programmable Interrupt Output
  • LED Outputs for Link and Activity Status Indication
  • On-Chip Termination Resistors for the Differential Pairs
  • HP Auto MDI/MDI-X to Reliably Detect and Correct Straight-Through and Crossover Cable Connections
  • Auto-Negotiation to Automatically Select the Highest Link-Up Speed (10/100 Mbps) and Duplex (Half/Full)
  • Power-Down and Power-Saving Modes
  • LinkMD ® TDR-Based Cable Diagnostics to Identify Faulty Copper Cabling
  • Parametric NAND Tree Support for Fault Detection Between Chip I/Os and the Board
  • Loopback Modes for Diagnostics
  • Built-In 1.2V Regulator for Core

Applications:

  • Game Consoles
  • IP Phones
  • IP Set-Top Boxes
  • IP TVs
  • LOM
  • Printers

Package:

  • 48-pin 7 mm x 7 mm LQFP

Features

  • Single-Chip 10BASE-T/100BASE-TX IEEE 802.3 Compliant Ethernet Transceiver
  • MII Interface Support
  • Back-to-Back Mode Support for a 100 Mbps Cop -per Repeater
  • MDC/MDIO Management Interface for PHY Reg -ister Configuration
  • Programmable Interrupt Output
  • LED Outputs for Link and Activity Status Indica -tion
  • On-Chip Termination Resistors for the Differential Pairs
  • Baseline Wander Correction
  • HP Auto MDI/MDI-X to Reliably Detect and Cor -rect Straight-Through and Crossover Cable Con -nections with Disable and Enable Option
  • Auto-Negotiation to Automatically Select the Highest Link-Up Speed (10/100 Mbps) and Duplex (Half/Full)
  • Power-Down and Power-Saving Modes
  • LinkMD ® TDR-Based Cable Diagnostics to Iden -tify Faulty Copper Cabling
  • Parametric NAND Tree Support for Fault Detec -tion Between Chip I/Os and the Board
  • HBM ESD Rating (6 kV)
  • Loopback Modes for Diagnostics
  • Single 3.3V Power Supply with V DD I/O Options for 1.8V, 2.5V, or 3.3V
  • Built-In 1.2V Regulator for Core
  • Available in 48-pin 7 mm x 7 mm LQFP Package

Applications

  • Game Consoles
  • IP Phones
  • IP Set-Top Boxes
  • IP TVs
  • LOM
  • Printers

Pin Configuration

FIGURE 2-1: 48-PIN 7 MM X 7 MM LQFP ASSIGNMENT (TOP VIEW)

TABLE 2-1: SIGNALS - KSZ8081MLX

Pin NumberPin NameType Note 2-1Description
1GNDGNDGround.
2GNDGNDGround.
3GNDGNDGround.
4VDD_!.2P1.2V Core V DD (power supplied by KSZ8081MLX). Decouple with 2.2 μF and 0.1 μF capacitors to ground, and join with Pin 31 by power trace or plane.
5NC-No Connect. This pin is not bonded and can be left floating.
6NC-No Connect. This pin is not bonded and can be left floating.
7VDDA_3.3P3.3V Analog V DD .
8NC-No Connect. This pin is not bonded and can be left floating.
9RXMI/OPhysical Receive or Transmit Signal (- differential).
10RXPI/OPhysical Receive or Transmit Signal (+ differential).
11TXMI/OPhysical Transmit or Receive Signal (- differential).
12TXPI/OPhysical Transmit or Receive Signal (+ differential).
13GNDGNDGround.
14XOOCrystal Feedback for 25 MHz Crystal. This pin is a no connect if an oscillator or external clock source is used.
15XIICrystal/Oscillator/External Clock Input (25 MHz ±50 ppm).
16REXTISet PHY Transmit Output Current. Connect a 6.49 kΩ resistor to ground on this pin.
17GNDGNDGround.
18MDIOIpu/ OpuManagement Interface (MII) Data I/O. This pin has a weak pull-up, is open- drain, and requires an external 1.0 kΩ pull-up resistor.
19MDCIpuManagement Interface (MII) Clock Input. This clock pin is synchronous to the MDIO data pin.
20RXD3/ PHYAD0Ipu/OMII Mode: MII Receive Data Output[3] (Note 2-2) Config. Mode: The pull-up/pull-down value is latched as PHYADDR[0] at the de-assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.
21RXD2/ PHYAD1Ipd/OMII Mode: MII Receive Data Output[2] (Note 2-2) Config. Mode: The pull-up/pull-down value is latched as PHYADDR[1] at the de-assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.
22RXD1/ PHYAD2Ipd/OMII Mode: MII Receive Data Output[1] (Note 2-2) Config. Mode: The pull-up/pull-down value is latched as PHYADDR[2] at the de-assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.

TABLE 2-1: SIGNALS - KSZ8081MLX (CONTINUED)

Pin NumberPin NameType Note 2-1Description
23RXD0/ DUPLEXIpu/OMII Mode: MII Receive Data Output[0] (Note 2-2) Config. Mode: The pull-up/pull-down value is latched as DUPLEX at the de- assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.
24GNDGNDGround.
25VDDIOP3.3V, 2.5V, or 1.8V Digital V DD .
26NC-No Connect. This pin is not bonded and can be left floating.
27RXDV/ CONFIG2Ipd/OMII Mode: MII Receive Data Valid Output. Config. Mode: The pull-up/pull-down value is latched as CONFIG2 at the de- assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.
28RXC/ B-CAST_OFFIpd/OMII Mode: MII Receive Clock Output. Config. Mode: The pull-up/pull-down value is latched as B-CAST_OFF at the de-assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.
29RXER/ ISOIpd/OMII Mode: MII Receive Error output Config. Mode: The pull-up/pull-down value is latched as ISOLATE at thede- assertion of reset See the Strap-In Options - KSZ8081MLX section for details.
30GNDGNDGround.
31VDD_1.2P1.2V Core V DD (power supplied by KSZ8081MLX). Decouple with 0.1 μF capacitor to ground, and join with Pin 4 by power trace or plane.
32INTRP/ NAND_Tree#Ipu/ OpuInterrupt Output: Programmable interrupt output. This pin has a weak pull-up, is open drain, and requires an external 1.0 kΩ pull-up resistor. Config. Mode: The pull-up/pull-down value is latched as NAND Tree# at the de-assertion of reset. See the Strap-In Options - KSZ8081MLX section for details.
33TXCIpd/OMII Mode: MII Transmit Clock Output. At the de-assertion of reset, this pin needs to latch in a pull-down value for normal operation. If MAC side pulls this pin high, see Register 16h, Bit [15] for solu - tion. It is better having an external pull-down resistor to avoid MAC side pulls this pin high.
34TXENIMII Mode: MII Transmit Enable input.
35TXD0IMII Mode: MII Transmit Data Input[0] (Note 2-3)
36TXD1IMII Mode: MII Transmit Data Input[1] (Note 2-3)
37GNDGNDGround.
38TXD2IMII Mode: MII Transmit Data Input[2] (Note 2-3)
39TXD3IMII Mode: MII Transmit Data Input[3] (Note 2-3)

Electrical Characteristics

T A = 25°C. Specification is for packaged product only.

TABLE 6-1: ELECTRICAL CHARACTERISTICS

ParametersSymbolMin.Typ.Max.UnitsNote
Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1Supply Current (V DDIO , V DDA_3.3 = 3.3V), Note 6-1
10BASE-TI DD1_3.3V-41-mAFull-duplex traffic @100% utilization
100BASE-TXI DD2_3.3V-47-mAFull-duplex traffic @100% utilization
EDPD ModeI DD3_3.3V-20-mAEthernet cable disconnected (Reg. 18h.11 = 0)
Power-Down ModeI DD4_3.3V-4-mASoftware power-down (Reg. 0h.11 = 1)
CMOS Level InputsCMOS Level InputsCMOS Level InputsCMOS Level InputsCMOS Level InputsCMOS Level InputsCMOS Level Inputs
Input High VoltageV IH2.0--VV DDIO = 3.3V
Input High VoltageV IH1.8--VV DDIO = 2.5V
Input High VoltageV IH1.3--VV DDIO = 1.8V
Input Low VoltageV IL--0.8VV DDIO = 3.3V
Input Low VoltageV IL--0.7VV DDIO = 2.5V
Input Low VoltageV IL--0.5VV DDIO = 1.8V
Input Current\I IN \--10
CMOS Level OutputsCMOS Level OutputsCMOS Level OutputsCMOS Level OutputsCMOS Level OutputsCMOS Level OutputsCMOS Level Outputs
Output High VoltageV OH2.4--VV DDIO = 3.3V
Output High VoltageV OH2.0--VV DDIO = 2.5V
Output High VoltageV OH1.5--VV DDIO = 1.8V
Output Low VoltageV OL--0.4VV DDIO = 3.3V
Output Low VoltageV OL--0.4VV DDIO = 2.5V
Output Low VoltageV OL--0.3VV DDIO = 1.8V
Output Tri-State Leakage\I OZ \--10
LED OutputLED OutputLED OutputLED OutputLED OutputLED OutputLED Output
Output Drive CurrentI LED-8-mAEach LED pin (LED0, LED1)
All Pull-Up/Pull-Down Pins (including Strapping Pins)All Pull-Up/Pull-Down Pins (including Strapping Pins)All Pull-Up/Pull-Down Pins (including Strapping Pins)All Pull-Up/Pull-Down Pins (including Strapping Pins)All Pull-Up/Pull-Down Pins (including Strapping Pins)All Pull-Up/Pull-Down Pins (including Strapping Pins)All Pull-Up/Pull-Down Pins (including Strapping Pins)
Internal Pull-Up Resistance304573V DDIO = 3.3V
Internal Pull-Up Resistancepu3961102V DDIO = 2.5V
Internal Pull-Up Resistance4899178V DDIO = 1.8V
Internal Pull-Down Resistancepd264379V DDIO = 3.3V
Internal Pull-Down Resistancepd3459113V DDIO = 2.5V
Internal Pull-Down Resistancepd5399200V DDIO = 1.8V
100BASE-TX Transmit (measured differentially after 1:1 transformer)100BASE-TX Transmit (measured differentially after 1:1 transformer)100BASE-TX Transmit (measured differentially after 1:1 transformer)100BASE-TX Transmit (measured differentially after 1:1 transformer)100BASE-TX Transmit (measured differentially after 1:1 transformer)100BASE-TX Transmit (measured differentially after 1:1 transformer)100BASE-TX Transmit (measured differentially after 1:1 transformer)
Peak Differential Output VoltageV O0.95-1.05V100Ω termination across differential output
Output Voltage ImbalanceV IMB--2%100Ω termination across differential output
Rise/Fall Timet r /t f3-5ns-
Rise/Fall Time Imbalance-0-0.5ns-
Duty Cycle Distortion---±0.25ns-
Overshoot---5%-
Output Jitter--0.7-nsPeak-to-peak

TABLE 6-1: ELECTRICAL CHARACTERISTICS (CONTINUED)

ParametersSymbolMin.Typ.Max.UnitsNote
10BASE-T Transmit (measured differentially after 1:1 transformer)10BASE-T Transmit (measured differentially after 1:1 transformer)10BASE-T Transmit (measured differentially after 1:1 transformer)10BASE-T Transmit (measured differentially after 1:1 transformer)10BASE-T Transmit (measured differentially after 1:1 transformer)10BASE-T Transmit (measured differentially after 1:1 transformer)10BASE-T Transmit (measured differentially after 1:1 transformer)
Peak Differential Output VoltageV P2.2-2.8V100Ω termination across differential output
Jitter Added---3.5nsPeak-to-peak
Rise/Fall Timet r /t f-25-ns-
10BASE-T Receive10BASE-T Receive10BASE-T Receive10BASE-T Receive10BASE-T Receive10BASE-T Receive10BASE-T Receive
Squelch ThresholdV SQ-400-mV5 MHz square wave
Transmitter - Drive SettingTransmitter - Drive SettingTransmitter - Drive SettingTransmitter - Drive SettingTransmitter - Drive SettingTransmitter - Drive SettingTransmitter - Drive Setting
Reference Voltage of I SETV SET-0.65-VR(I SET ) = 6.49 kΩ
100 Mbps Mode - Industrial Applications Parameters100 Mbps Mode - Industrial Applications Parameters100 Mbps Mode - Industrial Applications Parameters100 Mbps Mode - Industrial Applications Parameters100 Mbps Mode - Industrial Applications Parameters100 Mbps Mode - Industrial Applications Parameters100 Mbps Mode - Industrial Applications Parameters
Clock Phase Delay - XI Input to MII TXC Output-152025nsXI (25 MHz clock input) to MII TXC (25 MHz clock output) delay, refer - enced to rising edges of both clocks.
Link Loss Reaction (Indication) Timet llr-4.4-μsLink loss detected at receive differential inputs to PHY signal indication time for each of the following: 1. For LED mode 01, Link LED output changes from low (link-up) to high (link-down). 2. INTRP pin asserts for link-down status change.

Note 6-1 Current consumption is for the single 3.3V supply KSZ8081MLX device only, and includes the transmit driver current and the 1.2V supply voltage (V DD_1.2 ) that are supplied by the KSZ8081MLX.

Absolute Maximum Ratings

  • (V DD_1.2 ).................................................................................................................................................... -0.5V to +1.8V
  • (V DDIO , V DDA_3.3 ) ...................................................................................................................................... -0.5V to +5.0V
  • Input Voltage (all inputs) ........................................................................................................................... -0.5V to +5.0V
  • Output Voltage (all outputs) ...................................................................................................................... -0.5V to +5.0V
  • Lead Temperature (soldering, 10s) .......................................................................................................................+260°C
  • Storage Temperature (T )......................................................................................................................-55°C to +150°C

*Exceeding the absolute maximum rating may damage the device. Stresses greater than the absolute maximum rating may cause permanent damage to the device. Operation of the device at these or any other conditions above those spec -ified in the operating sections of this specification is not implied. Maximum conditions for extended periods may affect reliability.

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