US 11,812,527 B2
LED control device and lighting device including the same
Bongjin Lee, Hwaseong-si (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed on Sep. 20, 2022, as Appl. No. 17/948,701.
Claims priority of application No. 10-2021-0188580 (KR), filed on Dec. 27, 2021.
Prior Publication US 2023/0209677 A1, Jun. 29, 2023
Int. Cl. H05B 45/325 (2020.01); H05B 45/37 (2020.01); H05B 45/46 (2020.01)
CPC H05B 45/325 (2020.01) [H05B 45/37 (2020.01); H05B 45/46 (2020.01)] 20 Claims
OG exemplary drawing
 
1. A light emitting diode (LED) control device comprising:
a power supply connected to a first driving node and a second driving node through which an LED driver is configured to supply power to an LED module which comprises a first LED string configured to output light of a first color temperature and a second LED string configured to output light of a second color temperature;
a square wave generator configured to operate based on a first internal power supply voltage output from the power supply and generate a square wave;
a duty ratio controller configured to output a control signal based on the square wave, and change a slope of the control signal based on a change in a time constant; and
a switch circuit configured to operate based on a second internal power supply voltage output from the power supply, and control a ratio of a first current applied to the first LED string and a second current applied to the second LED string based on a change in the slope of the control signal.