LED driving device, lighting device, and vehicle-mounted display device
US11412594B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 2019 |
| Grant date | Aug 9, 2022 |
| Priority date | — |
| Expiry date | Feb 21, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An LED driving device includes a DC/DC controller which controls an output stage for supplying an output voltage to an LED; and a current driver which generates an output current of the LED. The current driver performs PWM dimming by turning on the output current in accordance with an LED-current-on period of a PWM dimming signal and turning off the output current in accordance with an LED-current-off period of the PWM dimming signal. The DC/DC controller includes a feedback control unit which performs feedback control for outputting a switching pulse to the output stage so as to make a cathode voltage of the LED equal to a reference voltage. A pulse addition control unit performs pulse addition control for adding a predetermined pulse number of additional switching pulses at a time of switching between the LED-current-on period and the LED-current-off period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.