Bypass protection circuit and light emitting diode driving device using the same

A light emitting diode (LED) driving device to drive a plurality of LED lamp bars, and each LED lamp bar comprising a plurality of LED groups composed of a plurality of LEDs connected in series, wherein each LED group has a common anode and a common cathode at two opposite ends, the LED driving device comprising:

• a power stage circuit to convert external power signals into driving signals to drive the LEDs;
• and
• at least one bypass protection circuit connected to the LED groups in parallel respectively, to provide a bypass path when any one LED is broken, the bypass protection circuit comprising:
• a switch circuit, comprising:
• a plurality of switch components, wherein each switch component is connected to one LED in parallel, when at least one LED is broken, the switch component corresponding to the at least one broken LED is switched on to provide a bypass path;
• an abnormal detection module to detect voltage of the LEDs respectively, and to output an abnormal signal when the at least one LED is broken;
• and
• a switch control module connected to the switch components and the abnormal detection module, to control the switch component corresponding to the at least one LED on according to the abnormal signal;
• and
• a capacitor connected between the common anode and the common cathode of the LEDs of the LED group, wherein the capacitor is charged by driving signals of the LEDs when the LEDs are operated according to a normal working mode or a first status of a burst dimming mode, and discharges to sustain an operating power of the switch circuit when the LEDs are operated according to a second status of the burst dimming mode.