SNLA487 May   2025 DP83826AE , DP83826AI

 

  1.   1
  2.   KSZ8081MNX/RNB to DP83826A System Rollover
  3.   Trademarks
  4. 1Purpose
  5. 2Required Changes
    1. 2.1 Strap Resistor Value
    2. 2.2 External Capacitor on Pin 2
    3. 2.3 Duplex Strap on Pin 16 (DP83826A Basic Mode)
    4. 2.4 Selecting 10M with Auto-Negotiation Enabled (DP83826A Basic Mode)
    5. 2.5 Configuring LED_1 for Tx and Rx Activity for EtherCAT Slave (DP83826A Basic Mode)
    6. 2.6 Thermal Pad Adjustments in Layout
    7. 2.7 Physical Layer ID Register
  6. 3Potential Changes
    1. 3.1 MDIO Pull-Up Resistor on Pin 11
    2. 3.2 MDIO Register Writes
    3. 3.3 Capacitors on Center Tap of Magnetics
  7. 4Informational Changes
  8. 5Pinout Mapping
    1. 5.1 Pin Mapping
  9. 6DP83826A Strap Configurations
    1. 6.1 Bootstrap Configurations

2.6 Thermal Pad Adjustments in Layout

The DP83826A thermal pad is smaller than KSZ8081. Table 2-4 lists the differences in package and DAP dimensions between the KSZ8081 and DP83826A. With the rollover between devices, there is still a sufficient gap between pins and DAP so that pins are not shorted.
Table 2-4 Package and DAP Dimension Differences
KSZ8081 DP83826A
Package dimensions 5 × 5mm 5 × 5mm
Maximum DAP dimensions 3 × 3mm 2.2 × 2.2mm

The recommended design for best practices on the layout is to match the solder paste stencil with the DP83826A thermal pad. This means reducing the solder paste from 3 × 3mm to 2.1 × 2.1mm.