TPS61310YFFR

PMIC - LED Drivers

LED drivers are the power interface between external AC or DC sources and the LED. LEDs have been commercially available since the 1960s and the need for LED drivers has been around for a similar amount of time. A simple linear regulator or a Zener diode might suffice for small constant power applications but for higher power applications and for dimming control, more robust and efficient drivers are needed. The Texas Instruments TPS61310YFFR is an example of a modern LED driver. This application note will explain the application field and working principle of the TPS61310YFFR.

Fields of Application

The TPS61310YFFR is a constant current boost LED driver designed for the industrial and commercial lighting markets. It is capable of powering up to 4 LEDs, which can be connected in parallel, and can provide up to 350 mA constant current. The device is also programmable and is capable of dimming and blinkingLEDs. It has a wide input voltage range of 4.5~42V, and is suitable for 24VAC or DC input voltage range. The output voltage can go as high as 38V, which makes it suitable for driving high power LEDs. The device also has a neat PWM dimming feature which can be used to control the brightness of the LED. The device is available in a 3mm x 3mm 16 pin WQFN package, making it small and easy to use.

Working Principle

The TPS61310YFFR is an inductive boost LED driver. It works in two modes, namely boost mode and skip mode. In the boost mode, an internal switch is turned on, in order to increase the output voltage above the input voltage. This is done by connecting a storage capacitor to the input and output of the device, and then turning on and off the switch. When the switch is off, the energy that was stored in the capacitor is discharged into the output and a voltage step-up is achieved. This mode is suitable for applications in which the input voltage is lower than the output voltage.

In the skip mode, a voltage clamping circuit is used to limit the output voltage to the input voltage and thus bypassing the boost stage. This means that the LED does not get powered up and hence the LED current is zero. This mode is suitable for applications in which the input voltage is higher than the output voltage. The device also includes active consumption circuit which enters skip mode automatically when the number of LEDs connected is greater than 4.

The device also includes a thermal regulation feature which helps in protecting the device from thermal stresses caused by excess power consumption. The device will instantly enter a protective skip mode if the device is overheating. This stops the power consumption to protect the device.

Conclusion

The TPS61310YFFR is an inductive boost LED driver designed by Texas Instruments for the industrial andcommercial lighting markets. It can support up to 4 LEDs in parallel and can be used for continuous or PWM dimming control for comfort lighting. The device also includes a thermal regulation feature to protect the device from overheating. It can drive LEDs up to 350 mA, and operate in a wide input voltage range from 4.5V to 42V. The 3mm x 3mm WQFN package makes it small and easy to use, and suitable for a wide range of lighting applications.