Intel DBPXA210, DBPXA250 Excessive Oscillator Output Voltage to Pextal Pin, Voltage Divider

Intel® DCPXA250 Processor Card

8.Excessive Oscillator Output Voltage to PEXTAL Pin

Problem: On systems using an oscillator to drive PEXTAL, the 3.3 V output from the oscillator is too high.

Implication: Possible damage to chip.

Workaround: Follow the steps below:

Note: These steps bring the oscillator voltage down to 1.1 V. The oscillator and core voltages need to be equal.

1.Attach one side of a 430-ohm resistor to the bottom (on the bottom of the processor card) of TP19 (ground).

2.Attach a 30-AWG wire from the remaining side of the 430-ohm to crystal X1 (The pin closest to the edge of the board).

3.Attach one side of a 620-ohm resistor to the junction of the wire and the 430-ohm resistor. The two resistors will “sandwich” the wire going to X1.

4.Attach another 30-AWG wire from the +3.3 V oscillator output (bottom of U7) to the open end of the 620-ohm resistor.

Status: Fixed

Board Rev: Rev C

Figure 9. Voltage Divider

Figure 10. Close-up of Voltage Divider

18 DBPXA250 and DBPXA210 Development Platforms Specification Update