IK3401

The IK3401 is a green mode PWM controller. It is specially designed for DVDP, STB and LCD monitor application.To minimize standby power consumption, a green-mode function provides off-time modulation to continuously decrease the switching frequency at light-load conditions.

Under zero-load conditions, the power supply enters burstmode. To avoid acoustic noise problem, the minimum PWM frequency set above 20KHz. This green-mode function enables the power supply to easily meet international power conservation requirements. To further reduce power consumption, IK3401 is manufactured by using the HV-CMOS process. This allows the lowest start-up current around 14uA, and the operating current is only 4mA. As a result, large start-up resistance can be used.

The maximum power can be limited constantly, regardless of the line voltage change using power limit function. The switching frequency is programmable or internally fixed to be 65kHz.

IK3401 integrates frequency modulation technique internally. The frequency jittering function helps reduce EMI emission of a power supply with minimum line filters. Also, its built-in synchronized slope compensation achieves stable peak-current-mode control. IK3401 provides many protection functions. In addition to cycle-by-cycle current limiting, the internal open-loop protection circuit ensures safety should an open loop or output short-circuit failure occurs. PWM output is disabled till VDD drops below the UVLO lower limit. Then, the controller starts up again. As long as VDD exceeds about 24V, the internal OVP circuit is triggered. For OVP and OTP, the protection mode can be chosen to be latch off or auto recovery.

IK3401 is available in an 8-pin DIP or SOP package.