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KSZ8081RND

Ethernet Physical-Layer Transceiver

The KSZ8081RND is a ethernet physical-layer transceiver from Micrel Inc.. View the full KSZ8081RND datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

KSZ8081RND shares its datasheet with KSZ8081RNA, whose page lists every part number it covers.

Official KSZ8081RND datasheet (PDF) — the source this page was extracted from.

Manufacturer

Micrel Inc.

Category

Interface ICs

Package

QFN-24 4x4mm

KSZ8081RND Key Specifications

ParameterValue
StandardIEEE 802.3 10Base-T/100Base-TX
MAC InterfaceRMII v1.2
Auto MDI/MDI-XHP Auto MDI/MDI-X
Cable DiagnosticsLinkMD TDR-based
Package Dimensions4mm x 4mm, 24-pin QFN
Core Supply Voltage3.3V single supply (built-in 1.2V regulator for core)
Digital I/O Voltage1.8V, 2.5V, or 3.3V
Management InterfaceMDC/MDIO (MIIM)
Operating Temperature0°C to 70°C (commercial, KSZ8081RNDCA)
Reference Clock (Optional Mode)25MHz crystal/clock input with 50MHz REF_CLK output
Reference Clock (KSZ8081RND Default)50MHz clock input to XI

KSZ8081RND Overview

Part: KSZ8081RNA/RND — Microchip Type: 10BASE-T/100BASE-TX Ethernet PHY Transceiver Description: Single-chip 10BASE-T/100BASE-TX IEEE 802.3 compliant Ethernet transceiver with RMII v1.2 interface support, integrated 1.2V regulator, and flexible 1.8V, 2.5V, or 3.3V digital I/O options.

Operating Conditions:

  • Supply voltage: 3.3V (single supply)
  • I/O voltage: 1.8V, 2.5V, or 3.3V
  • Reference clock: 25 MHz or 50 MHz

Absolute Maximum Ratings:

Key Specs:

  • Ethernet compliance: IEEE 802.3 (10BASE-T/100BASE-TX)
  • Interface: RMII v1.2
  • ESD rating (HBM): 6 kV
  • Crystal input: 25 MHz ±50 ppm (KSZ8081RNA default)
  • Oscillator/external clock input: 25 MHz ±50 ppm or 50 MHz ±50 ppm (KSZ8081RND default 50 MHz)
  • REXT resistor: 6.49 kΩ to ground
  • MDIO/INTRP pull-up resistor: 1.0 kΩ (external)

Features:

  • RMII back-to-back mode support for 100 Mbps copper repeater
  • MDC/MDIO management interface
  • Programmable interrupt output
  • LED outputs for Link and Activity status
  • On-chip termination resistors for differential pairs
  • HP Auto MDI/MDI-X
  • Auto-Negotiation (10/100 Mbps, Half/Full Duplex)
  • Power-Down and Power-Saving modes
  • LinkMD® TDR-Based Cable Diagnostics
  • Parametric NAND Tree Support
  • 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:

  • 24-pin 4 mm x 4 mm QFN

KSZ8081RND Features

  • Single-Chip 10BASE-T/100BASE-TX IEEE 802.3 Compliant Ethernet Transceiver
  • RMII v1.2 Interface Support with a 50 MHz Reference Clock Output to MAC, and an Option to Input a 50 MHz Reference Clock
  • RMII Back-to-Back Mode Support for a 100 Mbps Copper Repeater
  • 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
  • Baseline Wander Correction
  • HP Auto MDI/MDI-X to Reliably Detect and Correct Straight-Through and Crossover Cable Connections 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 Identify Faulty Copper Cabling
  • Parametric NAND Tree Support for Fault Detection 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 24-pin 4 mm x 4 mm QFN Package

KSZ8081RND Applications

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

KSZ8081RND Pin Configuration

FIGURE 2-1: 24-QFN PIN ASSIGNMENT (TOP VIEW)

KSZ8081RND 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-mALED0 pin
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 Resistance304573k ΩV DDIO = 3.3V
Internal Pull-Up Resistancepu3961102k ΩV DDIO = 2.5V
Internal Pull-Up Resistance4899178k ΩV DDIO = 1.8V
Internal Pull-Down Resistancepd264379k ΩV DDIO = 3.3V
Internal Pull-Down Resistancepd3459113k ΩV DDIO = 2.5V
Internal Pull-Down Resistancepd5399200k ΩV 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 O0.95-1.05V100 Ω termination across differential output
Output Voltage ImbalanceV IMB--2%100 Ω 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 P2.2-2.8V100 Ω 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 k Ω
REF_CLK OutputREF_CLK OutputREF_CLK OutputREF_CLK OutputREF_CLK OutputREF_CLK OutputREF_CLK Output
50 MHz RMII Clock Output Jitter--300-psPeak-to-peak. Applies only to RMII - 25 MHz Clock Mode.
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
Link Loss Reaction (Indication) Timet llr-4.4-μ sLink 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 KSZ8081RNA/RND device only, and includes the transmit driver current and the 1.2V supply voltage (V DD_1.2 ) that are supplied by the KSZ8081RNA/ RND.

KSZ8081RND 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 S )......................................................................................................................-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 specified in the operating sections of this specification is not implied. Maximum conditions for extended periods may affect reliability.

KSZ8081RND Package Information

Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
KSZ8081Microchip TechnologyVQFN-32 5x5mm
KSZ8081MLXMicrochip Technology48-pin 7 mm x 7 mm LQFP
KSZ8081RNAMicrel Inc.QFN-24 4x4mm
KSZ8081RNA/RNDMicrochip TechnologyQFN-24 4x4mm
KSZ8081RNACAMicrochip Technology24-VFQFN Exposed Pad
KSZ8081RNAIAMicrochip TechnologyQFN-24 4x4mm
KSZ8081RNBMicrochip Technology32-Pin QFN
KSZ8081RNDCAMicrochip TechnologyQFN-24 4x4mm

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All Interface ICs datasheetsAll Micrel datasheets (40)

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