US 7,321,206 B2
LED driving apparatus
Jeong-il Kang, Yongin-si (Korea, Republic of); and Sang-hoon Lee, Ulsan (Korea, Republic of)
Assigned to Samsung Electronics Co., Ltd., Suwon-si (Korea, Republic of)
Filed on Dec. 21, 2006, as Appl. No. 11/642,840.
Claims priority of application No. 10-2006-0013740 (KR), filed on Feb. 13, 2006.
Prior Publication US 2007/0188112 A1, Aug. 16, 2007
Int. Cl. G05F 1/00 (2006.01)
U.S. Cl. 315—291  [315/169.1; 315/224; 315/225; 315/119; 315/308; 345/82; 345/102] 18 Claims
OG exemplary drawing
 
1. An LED driving apparatus having an LED unit including at least one LED, and a current controlling unit for controlling the magnitude of current flowing through the LED unit in response to a control signal, comprising:
a voltage detecting unit for detecting a voltage across the LED unit; and
a control signal blocking unit for comparing the voltage detected by the voltage detecting unit with a reference voltage, and for preventing the control signal from being applied to the current controlling unit when the detected voltage is higher than the reference voltage.