For its part, the LM3407 is a high efficiency, constant current floating buck regulator. Providing up to 93% efficiency, the LM3407 serves to improve the overall thermal performance of the LED. Since the MOSFET is integrated into the device, it is extremely compact and simple to implement. An external 1% thick-film resistor additionally allows the converter output voltage to adjust as needed to deliver constant current within 10% accuracy to a connected LED string for highly accurate LED regulation. The LM3407 also features a DIM pin to enable PWM dimming, thermal shutdown, and over-current protection.