AP3436 (Obsolete)

Description

The AP3436/A is a step-down DC-DC converter with integrated power stage capable of driving up to 3A continuous output current. It integrates 2 N-channel power MOSFETs with low on-resistance. Current mode control provides fast transient response and cycle-by-cycle current limit. For AP3436, the regulator adopts current-mode in forced pulse-width modulation (PWM) mode with 1.25MHz switching frequency internally, which allows small-sized components, such as capacitors and inductors. This feature greatly simplifies the design of switch-mode power supplies. Under PWM mode, the device remains at the fixed PWM operation (typical at 1.25MHz), regardless of if the load current is high or low. For AP3436A, the regulator operates in either fixed PWM mode or a pulse-skipping modulation (PSM) mode depending on the different load conditions. The device can operate at typical 1.25MHz fixed switching frequency under heavy load condition. At light load, the regulator enters a PSM mode to minimize the switching loss by reducing the switching frequency. The AP3436/A provides EN function. Pulling this pin high statically enables the device while pulling the pin low statically for longer than 10μs will shut it down. Under Voltage Lockout is internally set at 2.75V for VCC detection. The output voltage startup ramp is control°C by the soft start. An open drain power good signal indicates the output is within 75% to 125% of its nominal voltage.

Application(s)

• Desktop & Notebook
• Low Voltage, High Density Power System
• Consumer Application Such as Set Top Box, LCD Display and CPE Equipment