The AP3105NA/NV/NL/NR is a low startup current, current mode PWM controller with green-mode power-saving operation. The PWM switching frequency at normal operation is set with 65kHz typically and the dithering of frequency will also improve the EMI feature. When the load decreases, the frequency will reduce and when at a very low load, the IC will enter the ‘burst mode’ to minimize switching loss.

 

About 20kHz frequency switching is to avoid the audible noise as well as reducing the standby loss. The skip mode point can be adjusted through the external resistor connected to the current sense resistor. The AP3105NA/NV/NL/NR features a lot of functions such as the Leading-Edge Blanking (LEB) of the current sensing, internal slope compensation and several protection functions including cycle-bycycle current limit (OCP), VCC Over Voltage Protection (VOVP), OTP and OLP protection. The versatile latch function can be set by the customer through few components.

 

This IC is available in SOT26 package.