AP3105NV Datasheet | BCD

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. A minimum 20k Hz frequency switching is to avoid the audible noise as well as to reduce the standby loss. A so-called VCC Maintain Mode is applied under light load to realize a stable output and to reduce the loss on the start-up resistor. The standby power of the system using AP3105NX can be reduced to 60m W at 230V input. AP3103 Frequency VFB Resistor Standby Performance External Protection VCC OVP Adjustable 4.5kΩ Better NA Auto-recoverable Auto-recoverable AP3105NX Fixed at 65k Hz 10kΩ Best By “CTRL” pin Latch /Auto-recoverable Latch /Auto-recoverable This application note includes detailed explanation of the IC’s major functions, some considerations about the PCB layout, and methods for reducing the standby power loss, and finally presents a demo design of a 12V 2A adaptor. 2. Function Description 2.1 CTRL Pin For some applications, the system requires external programmable protection function. The CTRL pin has two kinds of modes to trigger the protection: high level trigger and low level trigger. The low threshold voltage is 0.5V and high threshold voltage is 2.5V. When the CTRL pin voltage is lower than 0.5V or higher than 2.5V, latch or auto-restart protection will be triggered (different versions of AP3105NX offer different protection binations, which are shown in Table 2). Version AP3105NA VCC OVP Autorecoverable Latch Latch Autorecoverable OLP& FOCP Autorecoverable Autorecoverable Latch Autorecoverable CTRL (Low) Latch Latch Latch Autorecoverable CTRL (High) Autorecoverable Latch Latch Latch AP3105NV AP3105NL AP3105NR OLP & FOCP Table 2. Version Classification of AP3105NX Table 1. The Difference between AP3103/AP3105NX The AP3105NX integrates a lot of functions such as the Lead Edge Blanking (LEB) of the current sensing, internal slope pensation and several protection features which include...