# US 11,452,186 B1 · LED driver with rectified voltage monitor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,452,186 B1 - Document ID: US11452186B1 - Status: Granted - Kind: B1 - Application number: 17/529,858 - Filed: 2021-11-18 - Granted: 2022-09-20 - Earliest claimed: 2021-11-18 - Assignees: Cuvee Systems, Inc. - Applicants: Cuvee Systems, Inc. - Inventors: Dongsheng Zhou; Lanh Cong Nguyen - Web page: https://patentgrep.com/patent/US11452186B1 ## CPC - H05B 45/14: using electrical feedback from LEDs or from LED modules - H05B 45/355: Power factor correction [PFC]; Reactive power compensation - H05B 45/30: Driver circuits - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract Methods and systems for improved dimming of LED based illumination devices are described herein. An AC input voltage provided to an LED driver is rectified and the rectified signal is monitored by a Rectified Voltage Monitor (RVM) circuit. The RVM circuit generates a low voltage monitor signal indicative of the shape and peak voltage of the rectified signal. The monitor signal and the rectified signal are communicated to a power converter of the LED driver. The controller of the power converter employs the monitor signal to maintain efficiency and stability of the LED driver over an extended range of AC input voltage. The instantaneous voltage of the rectified signal is divided-down, and the peak value of the divided-down rectified signal is captured and stored on one or more capacitive elements. In another aspect, the peak voltage stored on one or more capacitive elements is less than 100 Volts. ## Claims ### Claim 1 An LED electrical power driver, comprising: a rectifier having a first input node and a second input node and a first output node and a second output node, wherein an Alternating Current (AC) input signal is provided across the first and second input nodes, and wherein a rectified signal is provided by the rectifier across the first and second output nodes; a power converter circuit having a first input node, a second input node, and a third input node, wherein the rectified signal is provided across the first and second input nodes of the power converter circuit; and a rectified voltage monitor electrically coupled to the first, second, and third input nodes of the power converter circuit, the rectified voltage monitor comprising: a voltage divider and peak detection circuit configured to divide the rectified signal by a predetermined factor to generate a divided-down rectified signal and detect a signal indicative of a peak voltage of the divided-down rectified signal; an electrical switching element having a control node, a first output node coupled to the second input node of the power converter circuit, and a second output node, wherein the signal indicative of the peak voltage of the divided-down rectified signal is communicated to the control node, wherein the electrical switching element is substantially conductive when the signal indicative of the peak voltage is greater than a first predetermined threshold value, and wherein the electrical switching element is substantially non-conductive when the signal indicative of the peak voltage is less than a second predetermined threshold value; and a voltage divider circuit including a first resistive element coupled between the first and third input nodes of the power converter circuit, a second resistive element coupled between the third input node of the power converter circuit and the second output node of the electrical switching element, and a third resistive element coupled between the third input node of the power converter circuit and the second input node of the power converter circuit. ### Claim 2 (depends on 1) The LED electrical power driver of claim 1, wherein the electrical switching element is a bipolar junction transistor or a field effect transistor. ### Claim 3 (depends on 1) The LED electrical power driver of claim 1, wherein the AC input signal is any AC voltage in a range from 80 Volts to 300 Volts. ### Claim 4 (depends on 1) The LED electrical power driver of claim 1, wherein the voltage divider and peak detection circuit includes a diode and a capacitor. ### Claim 5 (depends on 4) The LED electrical power driver of claim 4, wherein the peak voltage of the divided-down rectified signal stored on the capacitor is less than 100 Volts. ### Claim 6 (depends on 4) The LED electrical power driver of claim 4, wherein the peak voltage of the divided-down rectified signal stored on the capacitor is less than 10 Volts. ### Claim 7 (depends on 1) The LED electrical power driver of claim 1, wherein a voltage at the third input node of the power converter circuit is less than 2 Volts when the AC input signal is any AC voltage in a range from 80 Volts to 300 Volts. ### Claim 8 An LED electrical power driver, comprising: a rectifier configured to receive an Alternating Current (AC) input signal and generate a rectified signal; a power converter circuit electrically coupled to the rectifier, wherein the rectified signal is provided to the power converter circuit; a rectified voltage monitor electrically coupled to the power converter circuit, the rectified voltage monitor comprising: a voltage divider circuit electrically coupled to the power converter circuit, wherein the voltage divider circuit generates an output voltage signal communicated to the power converter circuit that is a fraction of the rectified signal, wherein the voltage divider circuit in a first state generates a first value of the output voltage that is a first fraction of the rectified signal, and wherein the voltage divider circuit in a second state generates a second value of the output voltage that is a second fraction of the rectified signal; a voltage divider and peak detection circuit configured to divide the rectified signal by a predetermined factor to generate a divided-down rectified signal and detect a signal indicative of a peak voltage of the divided-down rectified signal; and an electrical switching element having a control node, wherein the electrical switching element receives the divided-down rectified signal and configures the voltage divider circuit in the first state or the second state depending on a value of the divided-down rectified signal. ### Claim 9 (depends on 8) The LED electrical power driver of claim 8, wherein the electrical switching element is a bipolar junction transistor or a field effect transistor. ### Claim 10 (depends on 8) The LED electrical power driver of claim 8, wherein the AC input signal is any AC voltage in a range from 80 Volts to 300 Volts. ### Claim 11 (depends on 8) The LED electrical power driver of claim 8, wherein the voltage divider and peak detection circuit includes a diode and a capacitor. ### Claim 12 (depends on 11) The LED electrical power driver of claim 11, wherein the peak voltage of the divided-down rectified signal stored on the capacitor is less than 100 Volts. ### Claim 13 (depends on 11) The LED electrical power driver of claim 11, wherein the peak voltage of the divided-down rectified signal stored on the capacitor is less than 10 Volts. ### Claim 14 (depends on 8) The LED electrical power driver of claim 8, wherein a voltage at the third input node of the power converter circuit is less than 2 Volts when the AC input signal is any AC voltage in a range from 80 Volts to 300 Volts. ### Claim 15 A method comprising: rectifying an Alternating Current (AC) input signal to generate a rectified signal; dividing the rectified signal by a predetermined factor to generate a divided-down rectified signal; detecting a signal indicative of a peak voltage of the divided-down rectified signal; dividing a voltage of the rectified signal to generate an output voltage signal, wherein the dividing involves a voltage divider circuit in a first state to generate a first value of the output voltage signal that is a first fraction of the rectified signal, and wherein the dividing involves the voltage divider circuit in a second state to generate a second value of the output voltage signal that is a second fraction of the rectified signal; configuring the voltage divider circuit in the first state or the second state depending on a value of the signal indicative of the peak voltage of the divided-down rectified signal; and providing the rectified signal and the output voltage signal to a power converter circuit of an LED electrical power driver. ### Claim 16 (depends on 15) The method of claim 15, wherein the configuring the voltage divider circuit involves: switching an electrical switching element to a substantially conductive state when the signal indicative of the peak voltage of the divided-down rectified signal is greater than a first predetermined threshold value; and switching the electrical switching element to a substantially non-conductive state when the signal indicative of the peak voltage of the divided-down rectified signal is less than a second predetermined threshold value. ### Claim 17 (depends on 16) The method of claim 16, wherein the electrical switching element is a bipolar junction transistor or a field effect transistor. ### Claim 18 (depends on 15) The method of claim 15, wherein the AC input signal is any AC voltage in a range from 80 Volts to 300 Volts. ### Claim 19 (depends on 15) The method of claim 15, wherein the voltage output signal is less than 2 Volts when the AC input signal is any AC voltage in a range from 80 Volts to 300 Volts. ### Claim 20 (depends on 15) The method of claim 15, further comprising: storing the signal indicative of the peak voltage of the divided-down rectified signal on a capacitor, wherein the stored signal is less than 100 Volts.