Freescale 公司的34704A(8路)或34704B(5路)是多路开关电源稳压器,输出电压精度高达±2%,可用来管理各种多媒体应用的微处理器的电源.从单个电源输入(2.7V-5.5V),可提供5路或8路独立的输出电压.开关频率高达2MHz,非常适合手持设备的应用.本文介绍MC34704A/B主要特性,方框图,典型应用电路以及两种评估板电路图与材料清单(BOM):
Multiple Channel DC-DC Power Management IC
The 34704 is a multi-channel Power Management IC (PMIC) used to address power management needs for various multimedia application microprocessors. Its ability to provide either 5 or 8 independent output voltages with a single input power supply (2.7 and 5.5V) together with its high efficiency, make it ideal for portable devices powered up by Li-Ion/polymer batteries or for USB powered devices as well.
The 34704 is housed in a 7x7mm, Pb-free, QFN56 and is capable of operating at a switching frequency of up to 2MHz. This makes it possible to reduce external component size and to implement full space efficient power management solutions.
MC34704主要特性:
•8 DC/DC (34704A) or 5 DC/DC (34704B) switching regulators with up to ±2% output voltage accuracy
•Dynamic voltage scaling on all regulators.
•Selectable voltage mode control or current mode control on REG8
•I2C programmability..