Most mobile phones use white LEDs (WLEDs) as the backlight for their displays. Li-Ion batteries with an output range of 2.7 to 4.2 V are the most common power source for mobile phones. Since several WLEDs in series, each with forward voltages around 3.6 V, are typically used for the backlight, the backlight driver...
Read more »
LED Whitepapers
Reducing radiated EMI in WLED drivers
Compensating and measuring the control loop of a high-power LED driver
A mathematical model is always helpful in determining the optimal compensation components for a particular design. However, compensating the loop of a WLED currentregulating boost converter is a bit different than compensating the same converter configured to regulate voltage. Measuring the control loop with traditional methods is cumbersome because of low impedance at the...
Read more »
Driving a WLED does not always require 4 V
The popularity of white-light-emitting diodes (WLEDs) has skyrocketed, primarily because they are used to provide backlight to portable electronics displays. The common belief is that a single WLED requires a 4-V drive voltage. Since a Li-ion battery provides an average voltage of 3.6 V, the general industry consensus is that a step-up converter is...
Read more »
LED Lantern
Designers have the option of not only controlling the power stage, but regulating LED currents as well, eliminating the need for multiple components and reducing system cost. Systems can be designed to accurately control voltage and current regulation for precise light intensity and color mixing, temperature monitoring to prevent thermal runaway, intelligent/adaptive dimming, and fault detection (over voltage/current,...
Read more »
