AN-1425| Application Note

Differences Between National Semiconductor 10/100 Mb/s Ethernet Physical Layer Devices AN-1425

Differences Between National Semiconductor 10/100 Mb/s Ethernet Physical Layer Devices
1.0 Purpose
This is an informational document detailing differences between National Semiconductor 10/100 Mb/s Ethernet Physical Layer devices, DP8384x. Some of these points may need to be considered when updating an existing 10/100 Mb/s Ethernet design, using one of National Semiconductor's Ethernet Physical Layer (PHY) products, to the new DP83848 PHYTERTM product. Although the basic functions of the device are similar, differences include feature set, pin

National Semiconductor Application Note 1425 Brad Kennedy December 2005

functions, package and pinout, and possibly register operation. The impact to a design is dependant on which, and how, features of the previous device are used or implemented.

2.0 Hardware Differences
This section documents differences in the hardware as it relates to features, packages, operating voltages and environments, power requirements, and connections.

TABLE 1. Feature Differences System Interfaces: MII RMII SNI JTAG 100Base-FX Compliant Auto-MDIX Energy Detect LED Outputs INT Output CLK-to-MAC Output Temperature Range: 0 to 70 C -40 to 85 C -40 to 125 C * 5V tolerant TABLE 2. Package Differences DP83848 Package Footprint Package Drawing 48-LQFP 7x7mm VBH48A DP83847 56-LLP 9x9mm LQA56A DP83846 80-LQFP 14x14mm VHG80A DP83843 80-PQFP 14x14mm VJE80 Yes Available Available Yes No No Yes No No Yes No No DP83848 3.3V Yes Yes Available No Yes Yes 3 Yes Yes DP83847 5V* No No No No No No 6 No No DP83846 5V* No No No No No No 6 No No DP83843 5V No Yes No Yes No No 6 No No

TABLE 3. Supply Differences DP83848 Supply Voltage Active Power (Typ) 3.3v 267mW DP83847 3.3v 351mW DP83846 3.3v 495mW DP83843 5v 675mW

TABLE 4. Operating Temperature Differences Temperature Range 0 to 70 C -40 to 85 C -40 to 125 C DP83848 Yes Available Available DP83847 Yes No No DP83846 Yes No No DP83843 Yes No No

2005 National Semiconductor Corporation

AN201740

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