| CPC H05B 45/37 (2020.01) [H05B 45/325 (2020.01)] | 10 Claims |
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1. A LED circuit, comprising:
a current drive circuit;
an LED arrangement;
a current sensor for sensing when current flows through the LED arrangement, wherein the current sensor is coupled in series with the LED arrangement and wherein the series arrangement of the current sensor and the LED arrangement is coupled in parallel with an output capacitor;
the output capacitor, wherein the current drive circuit is adapted to drive a current through the LED arrangement, the current sensor and the output capacitor;
a control signal for setting the current level delivered by the current drive circuit;
an override arrangement for overriding the current level setting of the control signal to a default current level; and
a deactivating transistor for deactivating the override arrangement, wherein a control terminal voltage of the transistor is set by the sensor,
wherein the LED circuit is adapted to deactivate the override arrangement in response to the sensed current by the current sensor exceeding a threshold current, wherein the default current level is a maximum current level setting,
wherein the override arrangement comprises a circuit having a pull up transistor for pulling up the control signal to a default voltage when turned on, and isolating the default voltage from the control signal when turned off, and wherein the deactivating transistor when turned on, turns off the pull up transistor.
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