# US 11,116,058 B2 · LED dimming control circuit, dimming control method and LED power system thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,116,058 B2 - Document ID: US11116058B2 - Status: Granted - Kind: B2 - Application number: 16/699,861 - Filed: 2019-12-02 - Published: 2020-06-11 - Granted: 2021-09-07 - Earliest claimed: 2018-12-06 - Assignees: Silergy Semiconductor Technology (Hangzhou) LTD - Applicants: Silergy Semiconductor Technology (Hangzhou) LTD - Inventors: Longqi Wang; Qi'an Zeng - Web page: https://patentgrep.com/patent/US11116058B2 ## CPC - H05B 45/325: Pulse-width modulation [PWM] - H05B 45/10: Controlling the intensity of the light - H05B 45/32: Pulse-control circuits - Y02B 20/40: Control techniques providing energy savings, e.g. smart controller or presence detection - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract An LED dimming control circuit can include: a detection circuit configured to receive a dimming control signal, and to generate a detection signal for characterizing a type of the dimming control signal; and a dimming signal generation circuit configured to generate a dimming signal according to the detection signal and the dimming control signal, where a duty cycle of the dimming signal corresponds to the dimming control signal. A dimming control method can include: receiving a dimming control signal; detecting a number of rising or falling edges of the dimming control signal within a period of time to generate a detection signal; and determining a type of the dimming control signal in accordance with the detection signal. ## Claims ### Claim 1 A light-emitting diode (LED) dimming control circuit, comprising: a) a detection circuit configured to receive a dimming control signal, and to generate a detection signal for characterizing a type of the dimming control signal by detecting a number of rising or falling edges of the dimming control signal within a period of time by counting transitions of a clock signal that is generated by comparing the diming control signal against a reference voltage; b) a dimming signal generation circuit configured to generate a dimming signal according to the detection signal and the dimming control signal, wherein a duty cycle of the dimming signal corresponds to the dimming control signal; and c) a first conversion circuit configured to compare the dimming control signal against a triangular wave signal to generate a comparison result that is high when the triangular wave signal is greater than the dimming control signal. ### Claim 2 (depends on 1) The LED dimming control circuit of claim 1, wherein: a) when the number of rising or falling edges of the dimming control signal is less than a predetermined number, the dimming control signal is of a certain voltage signal, and the detection signal is in a first state; and b) when the number of rising or falling edges of the dimming control signal is not less than the predetermined number, the dimming control signal is of a pulse-width modulation (PWM) signal, and the detection signal is in a second state. ### Claim 3 (depends on 2) The LED dimming control circuit of claim 2, wherein when the dimming control signal is of the certain voltage signal, a dimmer for generating the dimming control signal operates in a resistance dimming mode or an analog dimming mode. ### Claim 4 (depends on 1) The LED dimming control circuit of claim 1, wherein the detection circuit only operates for the period of time after receiving the dimming control signal and is then disabled. ### Claim 5 (depends on 1) The LED dimming control circuit of claim 1, wherein the dimming signal generation circuit comprises: a) the first conversion circuit being enabled when the detection signal is in a first state; and b) a second conversion circuit that is enabled when the detection signal is in a second state. ### Claim 6 (depends on 5) The LED dimming control circuit of claim 5, wherein the second conversion circuit is configured to receive the dimming control signal with the type of a PWM signal, and to directly take or invert the dimming control signal as the dimming signal. ### Claim 7 (depends on 5) The LED dimming control circuit of claim 5, further comprising a voltage driving circuit having a first transistor and a first resistor coupled in series between a supply voltage and ground, and being configured to generate a voltage driving signal for generating a driving current to drive an LED load at a common node between the first transistor and the first resistor according to the dimming signal. ### Claim 8 (depends on 7) The LED dimming control circuit of claim 7, wherein a duty cycle of the dimming signal is complementary to or the same as a duty cycle of the voltage driving signal. ### Claim 9 (depends on 1) The LED dimming control circuit of claim 1, wherein the comparison result is directly taken as the dimming signal when the detection signal is in a first state. ### Claim 10 (depends on 1) The LED dimming control circuit of claim 1, further comprising a current source coupled in parallel with an input terminal of the LED dimming control circuit to provide current for matching a passive dimmer, wherein the current source is in parallel with the passive dimmer. ### Claim 11 (depends on 1) The LED dimming control circuit of claim 1, wherein the dimming signal generation circuit is configured to convert the dimming control signal to the dimming signal by a different conversion in accordance with the detection signal. ### Claim 12 (depends on 11) The LED dimming control circuit of claim 11, wherein when the dimming control signal is of a certain voltage signal, the duty cycle of the dimming signal corresponds to an amplitude of the dimming control signal. ### Claim 13 (depends on 11) The LED dimming control circuit of claim 11, wherein when the dimming control signal is of a PWM signal, the duty cycle of the dimming signal corresponds to a duty cycle of the dimming control signal. ### Claim 14 (depends on 1) An LED power system, comprising the LED dimming control circuit of claim 1, and further comprising: a) a dimmer configured to generate the dimming control signal; b) wherein the LED dimming control circuit is configured to generate a voltage driving signal according to the dimming control signal; and c) an LED driving circuit configured to generate a driving current to drive an LED load according to the voltage driving signal. ### Claim 15 A dimming control method for a light-emitting diode (LED), the method comprising: a) receiving a dimming control signal; b) detecting a number of rising or falling edges of the dimming control signal within a period of time to generate a detection signal by counting transitions of a clock signal that is generated by comparing the diming control signal against a reference voltage; c) determining a type of the dimming control signal in accordance with the detection signal; and d) comparing the dimming control signal against a triangular wave signal to generate a comparison result that is high when the triangular wave signal is greater than the dimming control signal. ### Claim 16 (depends on 15) The method of claim 15, further comprising: a) converting the dimming control signal into a dimming signal by a different conversion in accordance with the detection signal; and b) generating a voltage driving signal for generating a driving current to drive an LED load. ### Claim 17 (depends on 16) The method of claim 16, wherein when the dimming control signal with the type of a certain voltage signal, the detection signal is in a first state, and the dimming control signal is compared against a triangular wave signal to generate a comparison result as the dimming signal. ### Claim 18 (depends on 16) The method of claim 16, wherein when the dimming control signal with the type of a PWM signal, the detection signal is in a second state, the dimming control signal is directly taken or inverted as the dimming signal. ### Claim 19 (depends on 15) The method of claim 15, wherein: a) when the number of rising or falling edges of the dimming control signal is less than a predetermined number, the dimming control signal is of a certain voltage signal, and the detection signal is in a first state; and b) when the number of rising or falling edges of the dimming control signal is not less than the predetermined number, the dimming control signal is of a pulse-width modulation (PWM) signal, and the detection signal is in a second state.