驱动 WLED 不要求电压始终保持为 4V

驱动 WLED 不要求电压始终保持为 4V
Texas Instruments Incorporated Power Management




Driving a WLED does not always require 4 V
By Will Hadden
Power Management Products, Portable Power DC/DC Applications
The popularity of white-light-emitting diodes (WLEDs) has
Figure 1. Typical WLED I-V curves
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. 100
Since a Li-ion battery provides an average voltage of 3.6 V,
the general industry consensus is that a step-up converter