KSZ8081MNX/RNB
Physical Layer TransceiverThe KSZ8081MNX/RNB is a physical layer transceiver from Microchip Technology. View the full KSZ8081MNX/RNB datasheet below including key specifications, electrical characteristics, absolute maximum ratings.
KSZ8081MNX/RNB shares its datasheet with KSZ8081, whose page lists every part number it covers.
Official KSZ8081MNX/RNB datasheet (PDF) — the source this page was extracted from.
KSZ8081MNX/RNB Key Specifications
| Parameter | Value |
|---|---|
| Data Rates | 10/100 Mbps, half/full duplex |
| REXT Resistor | 6.49 kΩ |
| VDDIO Options | 1.8V, 2.5V, or 3.3V |
| ESD Rating (HBM) | 6 kV |
| Interface To MAC | RMII v1.2 (50 MHz reference clock output, input option) |
| Package Dimensions | 5 mm x 5 mm, 32-pin |
| Crystal/Clock Input | 25 MHz ±50 ppm |
| Management Interface | MDC/MDIO |
| Supply Voltage (Analog/Core) | 3.3V single supply (built-in 1.2V core regulator) |
| Operating Temperature (CA Suffix) | 0°C to 70°C |
| Operating Temperature (IA Suffix) | -40°C to 85°C |
KSZ8081MNX/RNB Overview
Part: KSZ8081 — Micrel Inc.
Type: 10Base-T/100Base-TX Ethernet Physical Layer Transceiver
Description: A single-supply 10Base-T/100Base-TX Ethernet physical-layer transceiver for data transmission and reception over standard CAT-5 UTP cable, featuring on-chip termination resistors, an integrated 1.2V regulator, and LinkMD TDR-based cable diagnostics.
Operating Conditions:
- Supply voltage: 3.3V (VDD I/O options for 1.8V, 2.5V, or 3.3V)
- Operating temperature: -40°C to +85°C
- Clock input: 25MHz crystal
Features:
- Single-chip 10Base-T/100Base-TX IEEE 802.3 compliant Ethernet transceiver
- MII (KSZ8081MNX) and RMII v1.2 (KSZ8081RNB) interface support
- HP Auto MDI/MDI-X to reliably detect and correct straight-through and crossover cable connections
- Auto-negotiation to automatically select the highest linkup speed (10/100Mbps) and duplex (half/full)
- LinkMD TDR-based cable diagnostics to identify faulty copper cabling
- Built-in 1.2V regulator for core
Applications:
- Game console
- IP phone
- IP set-top box
- IP TV
- LOM
- Printer
Package:
- 32-pin (5mm × 5mm) QFN package
KSZ8081MNX/RNB Features
- Single-chip 10Base-T/100Base-TX IEEE 802.3 compliant Ethernet transceiver
- MII interface support (KSZ8081MNX)
- RMII v1.2 Interface support with a 50MHz reference clock output to MAC, and an option to input a 50MHz reference clock (KSZ8081RNB)
- Back-to-back mode support for a 100Mbps copper repeater
- MDC/MDIO management interface for PHY register configuration
- Programmable interrupt output
- LED outputs for link, activity, and speed 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 linkup speed (10/100Mbps) 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 (6kV)
LinkMD is a registered trademark of Micrel, Inc.
Micrel Inc. · 2180 Fortune Drive · San Jose, CA 95131 · USA · tel +1 (408) 944-0800 · fax + 1 (408) 474-1000 · http://www.micrel.com
KSZ8081MNX/RNB Applications
- Game console
- IP phone
- IP set-top box
- IP TV
- LOM
- Printer
KSZ8081MNX/RNB Pin Configuration
32-Pin 5mm × 5mm QFN
KSZ8081MNX/RNB Electrical Characteristics
| Symbol | Parameter | Condition | Min. | Typ. | Max. | Units |
|---|---|---|---|---|---|---|
| Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) | Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) | Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) | Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) | Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) | Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) | Supply Current (V DDIO , V DDA_3.3 = 3.3V) (14) |
| I DD1_3.3V | 10Base-T | Full-duplex traffic @100% utilization | 41 | mA | ||
| I DD2_3.3V | 100Base-TX | Full-duplex traffic @100% utilization | 47 | mA | ||
| I DD3_3.3V | EDPD Mode | Ethernet cable disconnected (reg. 18h.11 = 0) | 20 | mA | ||
| I DD4_3.3V | Power-Down Mode | Software power-down (reg. 0h.11 = 1) | 4 | mA | ||
| CMOS Level Inputs | CMOS Level Inputs | CMOS Level Inputs | CMOS Level Inputs | CMOS Level Inputs | CMOS Level Inputs | CMOS Level Inputs |
| V IH | Input High Voltage | V DDIO = 3.3V | 2.0 | V | ||
| V IH | Input High Voltage | V DDIO = 2.5V | 1.8 | V | ||
| V IH | Input High Voltage | V DDIO = 1.8V | 1.3 | V | ||
| V IL | Input Low Voltage | V DDIO = 3.3V | 0.8 | |||
| V IL | Input Low Voltage | V DDIO = 2.5V | 0.7 | V | ||
| V IL | Input Low Voltage | V DDIO = 1.8V | 0.5 | |||
| \ | I IN \ | Input Current | V IN = GND ~ VDDIO | |||
| CMOS Level Outputs | CMOS Level Outputs | CMOS Level Outputs | CMOS Level Outputs | CMOS Level Outputs | CMOS Level Outputs | CMOS Level Outputs |
| V OH | Output High Voltage | V DDIO = 3.3V | 2.4 | V | ||
| V OH | Output High Voltage | V DDIO = 2.5V | 2.0 | V | ||
| V OH | Output High Voltage | V DDIO = 1.8V | 1.5 | V | ||
| V OL | Output Low Voltage | V DDIO = 3.3V | 0.4 | V | ||
| V OL | Output Low Voltage | V DDIO = 2.5V | 0.4 | V | ||
| V OL | Output Low Voltage | V DDIO = 1.8V | 0.3 | V | ||
| \ | I oz \ | Output Tri-State Leakage | ||||
| LED Output | LED Output | LED Output | LED Output | LED Output | LED Output | LED Output |
| I LED | Output Drive Current | Each LED pin (LED0, LED1) | 8 | mA |
KSZ8081MNX/RNB 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
KSZ8081MNX/RNB Package Information
Table 26. Compatible Single-Port 10/100 Magnetics
- Package information is correct as of the publication date. For updates and most current information, go to www.micrel.com.
32-Pin 5mm × 5mm QFN
32-Pin 5mm × 5mm QFN
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 Number | Manufacturer | Package |
|---|---|---|
| KSZ8081 | Microchip Technology | VQFN-32 5x5mm |
| KSZ8081MNX | Microchip Technology | QFN-32 5x5mm |
| KSZ8081MNX-EVAL | Microchip Technology | 32-Pin QFN |
| KSZ8081MNXCA | Microchip Technology | 32-VFQFN Exposed Pad |
| KSZ8081MNXIA | Microchip Technology | 32-Pin QFN |
| KSZ8081RNB | Microchip Technology | 32-Pin QFN |
| KSZ8081RNB-EVAL | Microchip Technology | 32-Pin QFN |
| KSZ8081RNBCA | Microchip Technology | 32-Pin QFN |
| KSZ8081RNBIA | Microchip Technology | 32-Pin QFN |
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