ZHCSHF4J May 2004 – January 2018 TPS51116
PRODUCTION DATA.
When RDS(on) sensing scheme is selected, the rectifying MOSFET’s on-resistance is used as this RS so that lower RDS(on) does not always promise better performance. In order to clearly detect inductor current, minimum RS recommended is to give 15 mV or larger ripple voltage with the inductor ripple current. This promises smooth transition from CCM to DCM or vice versa. Upper side of the RDS(on) is of course restricted by the efficiency requirement, and usually this resistance affects efficiency more at high-load conditions. When using external resistor current sensing, there is no restriction for low RDS(on). However, the current sensing resistance RS itself affects the efficiency