The TPS61166 is a boost converter with a 20-V rated integrated switch FET and power diode that drives up to 5 LEDs in series. This device integrates a high side switch FET that can turn on/off the LED current within 1-µs of the applied external PWM signal. The high side switch also provides input-to-output isolation during IC shutdown.

The default white LED current is set with the external sensor resistor R1, and the feedback voltage is regulated to 200-mV, as shown in the typical application circuit. The LED current can be adjusted using a pulse width modulation (PWM) signal through the PWM pin. The LED current is synchronized to the PWM signal. The device does not discharge the output ceramic capacitor during dimming, thus reducing audible noise when dimming.

Separating the IC input (VIN pin) and power stage input (VBAT pin) makes the device flexible enough to support single- or two-cell Li-ion battery applications. Other protection features include 1.1-A peak-to-peak over current protection (OCP), over voltage protection (OVP), over load protection (OLP), and thermal shutdown. The TPS61166 is available in a 2.5 mm × 2.5 mm SON package with thermal pad.