Specifications

Ref# 420826 Intel

Atom™ processor CE4100 65

Platform Design Guide

Intel Confidential

5.7 VREF Circuit

Figure 5-13 shows the DDR2/3 VREF circuit. A simple resistor divider with one percent or

better accuracy is used to generate DDR2/3 VREF power. The DDR2/3 VREF is a low-current

source (supplying input leakage and small transients). It must track 50 percent of DDR

power well over voltage, temperature, and noise. A single source will be used for VREF to

eliminate any variation and tracking of multiple generators.

Figure 5-13. DDR Vref Circuit Example

VREF

Intel

Atom™

processor

CE4100

DDR Power Well

1KΩ +/-1%

1KΩ +/- 1%

0.1uF

DDR Vref