IP电话的需要,在同一条电缆上的数据和电源。 48V高电压电源的需要,以减少在电缆的电压降。本应用笔记介绍了一个DC-DC升压转换器,可以提供所需的48V电源从12V电源通常在这样的系统的主机, 。它提供了低电压纹波,必须防止数据错误。Maxim > App Notes > AUTOMOTIVE
Keywords: High-Efficiency Boost Converter Provides 48V for IP Phones Dec 27, 2001
APPLICATION NOTE 911
High-Efficiency Boost Converter Provides 48V for IP Phones
IP phones require that data and power on the same cable. A high voltage power source of 48V is required, to
reduce the voltage drop in the cable. This application note describes a DC-DC step-up converter that can deliver
the required 48V supply, from the 12V source typically available in the host of such systems. It delivers low-
voltage ripple, essential to prevent data errors.
Isolation is provided by the 12V power-supply. For a system with one or two ports, a custom-designed DC-DC
converter is more suitable than power modules, or "bricks", since bricks tend to be b……