Boost regulator with integrated switch for LED backlighting
It integrates the power switch internally, rated for a 1.1 A switch current limit, and delivers a regulated output voltage up to 17 V — enough to drive a string of four to five white LEDs in series, depending on forward voltage. PWM dimming input allows brightness control directly from a microcontroller or backlight controller without an external DAC.
The 1.1 A switch current limit is the peak current the internal NMOS can handle before the cycle-by-cycle current limit engages. For a boost converter driving an LED string, this sets the maximum output current at a given input-to-output voltage ratio. At a typical 3.6 V input and 17 V output, the available LED current is roughly 200 mA — enough for a medium-brightness backlight in a 7-inch panel. Below 2.5 V the part will not start; above 6 V the absolute maximum is exceeded, so a pre-regulator or separate rail is needed if the system bus is 12 V.
The TPS61166DSKT comes in a 10-WFDFN exposed pad package (10-SON, 2.5x2.5 mm body). Surface-mount assembly per the standard reflow profile for MSL1/2 devices applies. The small 2.5 mm x 2.5 mm footprint suits space-constrained portable equipment such as handheld terminals, medical monitors, and portable instrumentation.