请问:
在TI给出的UCC2897A的应用PMP5426这个例子中,是不是没有过流保护这个功能,我查了资料,好像说是通过CS引脚有个功率限制作用。
daw y:
CS引脚可以实现逐脉冲限流,从而实现过流保护功能。
Johnsin Tao:
回复 daw y:
Hi有的,CS脚就是做电流保护的。过流保护是几乎所有电源芯片必须具备的功能。
jiayufei jia:
回复 Johnsin Tao:
你好:
过流保护现象是怎样的呢?我现在正在调试用 这个芯片做的电源,现象是电流大于一定值时输出电压下降,但是降不到零,是这样吗???
jiayufei jia:
回复 daw y:
你好:可以简单解释一下吗?
Johnsin Tao:
回复 jiayufei jia:
HiThis pin senses the peak current utilized for current-mode control and for currentlimiting functions. The peak signal is applied to this pin before pulse-by-pulse current limiting activates and is approximately 0.5 VCS is a direct input to the PWM and current-limit comparators of the UCC2897A controller. The CS pin never connects directly across the current-sense resistor (RCS) of the power converter. A small, customary R-C filter between the current-sense resistor and the CS pin is necessary to accommodate the proper operation of the onboard slope-compensation circuit and in order to protect the interna- discharge transistor connected to the CS pin (RF1, CF).