VIA Technologies EPIA-M Mini-ITX Manual de usuario descargar pdf (Pagina 11)

Mini-ITX Power Solutions Andrei Bulucea

Automotive Solutions Ituner Networks

DC-DC converters - 11 - Automotive Applications

IA 5000

DC-DC Converters

Another alternative to traditional ATX power supplies is the use of several DC-DC converters to

provide power to all the necessary rails from a singe input, usually running at 12 V. This is not a

new concept, laptop computers have been using DC-DC converters for a long time.

However, with the introduction of low power mini-ITX boards DC-DC conversion is the natural

choice, especially when the designer does not have enough room for a traditional ATX power

supply.

Another advantage of using DC-DC converters is that they are 100% silent. The internal

oscillators of an DC-DC converter operate at 300-600Khz, therefore they do not produce any

audible noise. By using highly efficient ‘step down’ BUCK converters (linear regulators are very

inefficient), the heat dissipation is small. For example, a 60 W DC-DC converter does not require

any active cooling and it can operate at 40-50 Celsius with no heat sinks.

A single 12 V input is used to step down to 3.3,and 5 V and invert to -12 V and -5 V (if needed).

Also, 5 V SB power is provided for sleep functions. The 12 V output can be regulated by boosting

5 V to 12 V or simply switching ON/OFF with a P-channel FET (see below for more information

on car applications).

There are several DC-DC converter manufacturers. However, the DC-DC converters developed

by mini-box.com are designed specifically for the VIA mini-ITX boards:

A unique snap-in daughter-board design allows you to plug the DC-DC converter directly into the

mother board’s ATX connector, thus reducing space and not using the messy ATX power cable

extenders. At this time, mini-box.com provides 2 types of snap-in power modules. The PW-60

was designed for the EPIA-5000, EPIA-800, EPIA-V while the PW-70 was designed for the EPIA-

M form factor.

These DC-DC ATX power converters operate from 12 V and are highly efficient. Applications

range from portable to automotive and small form factor embedded robotics, or solar powered

computer systems.

1 2 ... 6 7 8 9 10 11 12 13 14 15 16 ... 24 25

Sin comentarios

VIA Technologies EPIA-M Mini-ITX Manual de usuario Pagina 11