LED driver chip SN3910 performance characteristics and application design

SN3910 is a peak current sensing buck LED driver that operates in constant off-time mode. It allows voltage sources ranging from DC8-45V or AC110V/220V to drive high-brightness LEDs.

SN3910 can adjust LED brightness according to PWM signals, and the acceptable PWM control signal duty cycle is 0-100%. It also includes a 50-240mV linear dimming input that can be used for LED current linear adjustment and temperature compensation.

SN3910 uses peak current mode control. The controller does not require any loop compensation to achieve good output current regulation. The response time of PWM dimming is determined by the rise and fall rates of the inductor current, resulting in very short rise and fall times.

2. SN3910 Typical Application Circuit

Figure 1 SN3910 typical application circuit

3. SN3910 3W 350mA Power Supply Design

Figure 2 SN3910 3W 350mA power supply design