Nettop Platform for 2008 System Design White Paper

System Configuration

White Paper 19

4.3 Power Supply

4.3.1 Power Supply Requirement

This platform requires a typical desktop 5 rail output power supply for the whole

system. The motherboard is powered from a 20 pin main connector and a 2x2

connector. The common internal power supply can provide a cost effective solution for

the platform. The detailed electrical requirement can be found in the Power Supply

Design guide for Desktop form factors (www.formfactors.org). For building an ultra

small form factor system or Energy Star compliant system, some recommendation is

provided in the following section.

Typical Power Distribution

Power supply should meet the minimum power distribution requirement in

Table 7.

Table 7 Typical Power Distribution

Output Minimum Current (A)

Maximum Current (A) Peak Current (A)

12 VDC 0.2 3 —

5 VDC

0.2 6 —

3.3 VDC

0.1 9 —

-12 VDC — 0.3 —

5 VSB — 2 2.5

Total Power 70 W

NOTES:

1. Peak currents may last up to 17 seconds with not more than one occurrence per minute.

2. Total combined output of 3.3 V and 5 V is ≤ 50 W.

Main Power Connector

This motherboard requires a 20 pin main power connector. A 24 pin main power

connector is acceptable. The motherboard designer needs to make sure that not to put

any tall components (≦3.5 mm), such as capacitors in the area where the 4 extra pins

will be.

Serial ATA* Power Connector

Make sure the power supply has Serial ATA* power connector if the system has Serial

ATA devices.

Note: Other electrical and mechanical specifications can be found in the Power Supply

Design Guide for Desktop Platform Form Factors (www.formfactors.org)