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US 2022/0070983 A1Published application
LED Driving Device and LED Driving Method
AssigneeSilicon Works Co., Ltd.
InventorsJi Hwan Kim, Kyeong Rok Lee, Jong Hyun Yoon
Life of this patent
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Abstract
The present disclosure relates to an LED driving technique. The present disclosure provides a technique of measuring a time for reaching a forward voltage of a currently driven LED by comparing a forward voltage sensed in a previous scan line and an LED voltage sensed in a current scan line and for compensating for an ON period of a PWM (pulse width modulation) signal by the measured time for reaching the forward voltage.
Claims15
An LED driving device comprising:
- a driving current source configured to supply a driving current to a driving line to which a plurality of LEDs are connected;
- a driving control circuit configured to control a supply time of the driving current to the driving line according to a pulse width modulation (PWM) signal;
- a sample and hold circuit configured to sense a one-side voltage of an LED and to hold a voltage corresponding to a forward voltage;
- and
- a PWM compensating circuit configured to, during a time period in which one LED is connected to the driving line, measure a first time for a one-side voltage of the one LED to reach a voltage held regarding another LED and to compensate for the PWM signal according to the first time.
2 more elements
An LED driving device comprising:
- a driving current source configured to supply a driving current to a first LED during a first scan time and to supply the driving current to a second LED during a second scan time;
- a sample and hold circuit configured to, during the first scan time, sense a one-side voltage of the first LED and to hold a voltage corresponding to a forward voltage;
- and
- a compensating circuit configured to, during the second scan time, measure a first time for a one-side voltage of the second LED to reach the voltage held regarding the first LED and to control a supply time of the driving current to the second LED according to the first time.
1 more element
A method for driving a plurality of LEDs disposed in a panel, the method comprising:
- connecting a first LED to one driving line according to a first scan signal;
- supplying a driving current to the first LED through the one driving line and sensing and holding a forward voltage of the first LED;
- connecting a second LED to the one driving line according to a second scan signal;
- supplying the driving current to the second LED through the one driving line and measuring a first time for a one-side voltage of the second LED to reach the forward voltage of the first LED;
- and
- controlling a supply time of the driving current to the second LED according to the first time.
3 more elements
Dependencies are inferred from the claim text.