Constant voltage and constant current driver circuit
A driver circuit for delivering a generally constant voltage to a load is disclosed. The driver circuit includes a source of incoming AC power, a rectifier, and a constant voltage driver. The rectifier is connected to the source of incoming AC power and produces a DC voltage. The constant voltage driver receives the DC voltage from the rectifier. The constant voltage driver includes a selectively activated switching element for receiving the DC voltage, a controller, and an output line. The controller receives the DC voltage and is configured to send a drive signal to the switching element in order to activate the switching element. The output line provides the generally constant voltage to the load.
1. A driver circuit for delivering a generally constant voltage and generally constant current to a load comprising a plurality of LED arrays, the driver circuit comprising:
a source of incoming AC power;
a rectifier connected to the source of incoming AC power, the rectifier producing a DC voltage;
a constant voltage driver for receiving the DC voltage from the rectifier, the constant voltage driver comprising:
a selectively activated switching element for receiving the DC voltage;
a controller for receiving the DC voltage, the controller configured to send a drive signal to the switching element to activate the switching element;
an output line providing a generally constant voltage; and
a plurality of constant current drivers each directly in communication with the output line of the constant voltage driver to receive the generally constant voltage, wherein each of the plurality of constant current drivers provides a substantially constant current to a corresponding one of the plurality of LED arrays.
2. The driver circuit of claim 1 , further comprising a buck converter in communication with the switching element, wherein the buck converter receives the DC voltage if the switching element is activated.
3. The driver circuit of claim 2 , wherein the buck converter includes a freewheeling diode, a primary winding, and a secondary winding.
4. The driver circuit of claim 3 , wherein the secondary winding is part of a voltage regulator circuit.
5. The driver circuit of claim 3 , wherein a voltage from the primary winding is stepped down by the secondary winding before the voltage is sent to a linear voltage regulator.
6. The driver circuit of claim 1 , wherein the switching element is a high-side switching element.
7. The driver circuit of claim 1 , wherein the constant voltage driver includes a floating ground.
8. The driver circuit of claim 1 , wherein the constant voltage driver is grounded to earth.
9. The driver circuit of claim 1 , wherein the load is driven using pulse width modulated (PWM) control or linear control.
10. The driver circuit of claim 1 , wherein the plurality of constant current drivers each includes a current controller for providing a generally constant current to the load.
11. The driver circuit of claim 1 , wherein the plurality of constant current drivers are each grounded to earth.
12. The driver circuit of claim 1 , wherein the plurality of constant current drivers each includes a floating ground.
13. The driver circuit of claim 1 , wherein the plurality of LED arrays are based on red, green, blue (RGB) color mixing, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another to produce a light output of a specified color.
14. The driver circuit of claim 1 , wherein the plurality of LED arrays comprise white LEDs, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another in order to modify a color temperature of the white LEDs.
15. The driver circuit of claim 1 , wherein the plurality of LED arrays comprise white LEDs, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another such that as the LED arrays are dimmed, a color temperature of the plurality of LED arrays is increased.
16. The driver circuit of claim 1 , further comprising an electromagnetic interference (EMI) filter connected to the rectifier.
17. A driver circuit for delivering a generally constant voltage and generally constant current to a plurality of LED arrays, the driver circuit comprising:
a source of incoming AC power;
a rectifier connected to the incoming source of AC power, the rectifier producing a DC voltage;
a constant voltage driver for receiving the DC voltage from the rectifier, wherein the constant voltage driver includes a floating ground, the constant voltage driver comprising:
a selectively activated high-side switching element for receiving the DC voltage;
a controller for receiving the DC voltage, the controller configured to send a drive signal to the high-side switching element to activate the high-side switching element; and
an output line providing a generally constant voltage; and
plurality of constant current drivers each directly in communication with the output line of the constant voltage driver to receive the generally constant voltage, wherein each of the plurality of constant current drivers provides a substantially constant current to a corresponding one of the plurality of LED arrays.
18. The driver circuit of claim 17 , further comprising a buck converter in communication with the high-side switching element, wherein the buck converter receives the DC voltage if the high-side switch is activated.
19. The driver circuit of claim 18 , wherein the buck converter includes a freewheeling diode, a primary winding, and a secondary winding.
20. The driver circuit of claim 19 , wherein the secondary winding is part of a voltage regulator circuit.
21. The driver circuit of claim 19 , wherein a voltage from the primary winding is stepped down by the secondary winding before the voltage is sent to a linear voltage regulator.
22. The driver circuit of claim 17 , wherein the plurality of constant current drivers each includes a current controller for providing a generally constant current to the load.
23. The driver circuit of claim 17 , wherein the plurality of constant current drivers are each grounded to earth.
24. The driver circuit of claim 17 , wherein the plurality of LED arrays are based on red, green, blue (RGB) color mixing, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another to produce a light output of a specified color.
25. The driver circuit of claim 17 , wherein the plurality of LED arrays comprise white LEDs, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another in order to modify a color temperature of the white LEDs.
26. The driver circuit of claim 17 , wherein the plurality of LED arrays comprise white LEDs, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another such that as the LED arrays are dimmed, a color temperature of the plurality of LED arrays is increased.
27. A driver circuit for delivering a generally constant voltage and generally constant current to a plurality of LED arrays, the driver circuit comprising:
a source of incoming AC power;
a rectifier connected to the incoming source of AC power, the rectifier producing a DC voltage;
a constant voltage driver for receiving the DC voltage from the rectifier, wherein the constant voltage driver is grounded to earth, the constant voltage driver comprising:
a selectively activated switching element for receiving the DC voltage;
a controller for receiving the DC voltage, the controller configured to send a drive signal to the switching element to activate the switching element; and
an output line providing a generally constant voltage; and
plurality of constant current drivers each directly in communication with the output line of the constant voltage driver to receive the generally constant voltage, wherein each of the plurality of constant current drivers provides a substantially constant current to a corresponding one of the plurality of LED arrays.
28. The driver circuit of claim 27 , further comprising a buck converter in communication with the switching element, wherein the buck converter receives the DC voltage if the switch is activated.
29. The driver circuit of claim 28 , wherein the buck converter includes a freewheeling diode, a primary winding, and a secondary winding.
30. The driver circuit of claim 29 , wherein the secondary winding is part of a voltage regulator circuit.
31. The driver circuit of claim 29 , wherein a voltage from the primary winding is stepped down by the secondary winding before the voltage is sent to a linear voltage regulator.
32. The driver circuit of claim 27 , wherein the plurality of constant current drivers each includes a current controller for providing a generally constant current to the load.
33. The driver circuit of claim 27 , wherein the plurality of constant current drivers each include a floating ground.
34. The driver circuit of claim 27 , wherein the plurality of LED arrays are based on red, green, blue (RGB) color mixing, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another to produce a light output of a specified color.
35. The driver circuit of claim 27 , wherein the plurality of LED arrays comprise white LEDs, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another in order to modify a color temperature of the white LEDs.
36. The driver circuit of claim 27 , wherein the plurality of LED arrays comprise white LEDs, and wherein each of the plurality of constant current drivers drives each of the plurality of LED arrays separately from one another such that as the LED arrays are dimmed, a color temperature of the plurality of LED arrays is increased.
37. A driver circuit for delivering a generally constant voltage and generally constant current to a load, the driver circuit comprising:
a source of incoming AC power;
a rectifier connected to the source of incoming AC power, the rectifier producing a DC voltage;
a constant voltage driver for receiving the DC voltage from the rectifier, the constant voltage driver comprising:
a selectively activated switching element for receiving the DC voltage;
a controller for receiving the DC voltage, the controller configured to send a drive signal to the switching element to activate the switching element;
an output line providing a generally constant voltage;
at least one constant current driver in communication with the output line of the constant voltage driver to receive the generally constant voltage; and
a buck converter in communication with the switching element, wherein the buck converter receives the DC voltage if the switching element is activated.
38. The driver circuit of claim 37 , wherein the buck converter includes a freewheeling diode, a primary winding, and a secondary winding.
39. The driver circuit of claim 38 , wherein the secondary winding is part of a voltage regulator circuit.
40. The driver circuit of claim 38 , wherein a voltage from the primary winding is stepped down by the secondary winding before the voltage is sent to a linear voltage regulator.
41. The driver circuit of claim 37 , wherein the switching element is a high-side switching element.
42. The driver circuit of claim 37 , wherein the constant voltage driver includes a floating ground.
43. The driver circuit of claim 37 , wherein the constant voltage driver is grounded to earth.