Dimming controlling circuit for LED
First Claim
1. A dimming controlling circuit for LED, comprising:
- a switch configured to connect a main circuit and a power grid;
a switch-on duration controlling circuit configured to output a switch-on duration controlling signal according to action times of the switch;
a switch-off controlling circuit configured to compare a voltage of the switch-on duration controlling signal and a voltage of a signal from a terminal of a switch transistor in the main circuit to obtain a comparison result and to output a switch-off controlling signal according to the comparison result;
a switch-on controlling circuit configured to generate a switch-on controlling signal after a first preset duration since receiving the switch-off controlling signal; and
a logic unit configured to output a switch transistor controlling signal according to the switch-off controlling signal and the switch-on controlling signal,wherein the switch-on duration controlling circuit comprises;
a power generating circuit configured to generate a first voltage according to an input voltage;
a detecting circuit configured to detect the input voltage, to output an invalid shift controlling signal when determining the input voltage reaches a first threshold voltage and to output a valid shift controlling signal when determining the input voltage descends below a second threshold voltage and above the third threshold voltage;
a shift register configured to output a shift result according to the invalid or valid shift controlling signal;
a resetting circuit configured to reset the shift register to zero;
a decoding circuit configured to decode according to the shift result to obtain a decoding result; and
a selecting circuit configured to select a voltage corresponding to the switch-on duration controlling signal according to the decoding result.
3 Assignments
0 Petitions
Accused Products
Abstract
A dimming controlling circuit for LED includes: a switch configured to connect a main circuit and a power grid; a switch-on duration controlling circuit configured to output a switch-on duration controlling signals according to action times of the switch; a switch-off controlling circuit configured to output a switch-off controlling signal according to a comparison result of the voltages of the switch-on duration controlling signal and of a signal from a terminal of a switch transistor in the main circuit; a switch-on controlling circuit configured to generate a switch-on controlling signal after a first preset duration since receiving the switch-off controlling signal; and a logic unit configured to output a switch transistor controlling signal.
6 Citations
12 Claims
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1. A dimming controlling circuit for LED, comprising:
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a switch configured to connect a main circuit and a power grid; a switch-on duration controlling circuit configured to output a switch-on duration controlling signal according to action times of the switch; a switch-off controlling circuit configured to compare a voltage of the switch-on duration controlling signal and a voltage of a signal from a terminal of a switch transistor in the main circuit to obtain a comparison result and to output a switch-off controlling signal according to the comparison result; a switch-on controlling circuit configured to generate a switch-on controlling signal after a first preset duration since receiving the switch-off controlling signal; and a logic unit configured to output a switch transistor controlling signal according to the switch-off controlling signal and the switch-on controlling signal, wherein the switch-on duration controlling circuit comprises; a power generating circuit configured to generate a first voltage according to an input voltage; a detecting circuit configured to detect the input voltage, to output an invalid shift controlling signal when determining the input voltage reaches a first threshold voltage and to output a valid shift controlling signal when determining the input voltage descends below a second threshold voltage and above the third threshold voltage; a shift register configured to output a shift result according to the invalid or valid shift controlling signal; a resetting circuit configured to reset the shift register to zero; a decoding circuit configured to decode according to the shift result to obtain a decoding result; and a selecting circuit configured to select a voltage corresponding to the switch-on duration controlling signal according to the decoding result. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification