LED电平移位器包括故障检测

摘要：虽然许多LED驱动IC工作在相对较低的电压，可以工作在更高的电压，从而驱动串联多个LED ，通过增加一个共同的基晶体管的电平转换器，这种IC （ MAX6974 ）所示。

Maxim > App Notes > Display Drivers
Keywords: LED drivers, multiple-LED drivers, NPN transistors, level shifters, fault detection, open-circuit detection Dec 22, 2010

APPLICATION NOTE 4549
LED Level Shifter Includes Fault Detection


Abstract:Although many LED-driver ICs operate at relatively low voltage, you can operate at higher voltage and thereby drive
multiple LEDs in series, by adding a common-base-transistor level shifter to this IC (MAX6974) as shown.

A similar version of this article appeared in the October 18, 2007 issue of EE Times magazine.

The relatively low operating voltage of many LED-driver ICs prevents them from driving multiple LEDs in series, but you can
circumvent this limitation by adding a common-base-transistor level shifter as shown in Figure 1. NPN transist