POWER SUPPY CIRCUIT

• US 20100253302A1
• Filed: 11/06/2008
• Published: 10/07/2010
• Est. Priority Date: 11/07/2007
• Status: Active Grant

• Current Assignee: Philips Lighting BV (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Van Den Broek, Vincent Gerardus Petrus Cornelis, Deppe, Carsten, Peeters, Henricus Marie, Otte, Rob
• Granted Patent: US 8,773,087 B2
• Time in Patent Office: Days
• US Class Current: 323/282
• CPC Class Codes: H02M 3/155 using semiconductor devices only
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/375 using buck topology
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: H05B 45/385 using flyback topology
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines

Abstract

The invention relates to a power supply circuit (10) and methods for supplying electrical power to at least one load output. The circuit comprises a main power supply unit (12) with a voltage input (14), a main switching element (26) and a reactive element (28). The switching element (26) is controllable to deliver an output voltage or current (I out). Output units (20a, 20b, 20c) with load outputs are connected to a main power supply unit (12). In order to drive loads connected to the load outputs, e.g. LEDs, OLEDs or laser diodes, with exact pulses, each output unit (20a, 20b, 20c) has a load switching element (38) to connect or disconnect the main power supply unit (12) to or from the load output. There are further provided switched capacitor units (34), each with a capacitor (C) and a capacitor switching element (40). The capacitor units may be operated such that the capacitors remain essentially charged at different voltage levels. According to a second aspect of the invention, each output unit (20a, 20b, 20c) has a switched capacitor unit (34) with a capacitor (C) and a capacitor switching element (40) connected to the load output. The load switching element (38) and the capacitor switching elements (40) are controlled synchronously.

Claims

1. Power supply circuit comprising:

a main power supply unit comprising a voltage input, at least one main switching element, and at least one reactive element, wherein said switching element is controllable to deliver an output voltage (V_out) and/or current (I_out), and

at least one output unit connected to said main power supply unit, comprising;

a load output,

a load switching element connected to said load output to connect or disconnect said main power supply unit to or from said load output,

a first switched capacitor unit connected to said load output and comprising a first capacitor (Ca) and a first capacitor switching element, and

a second switched capacitor unit connected to said load output and comprising a second capacitor (Cb) and a second capacitor switching element.

2. Circuit according to claim 1, wherein each of said switched capacitor units comprises said capacitor (Ca, Cb) and said capacitor switching element connected in series.

3. Circuit according to claim 1, wherein said switched capacitor units are connected to said main power supply unit in parallel with said load output and/or said load switching element.

4. Circuit according to claim 1, wherein a plurality of output units are connected to said main power supply unit in parallel.

5. Circuit according to claim 1, further comprising a control means for controlling at least said load switching element and said first and second capacitor switching elements, wherein said load switching element is controlled synchronously with a selected one of said first and said second capacitor switching elements.

6. Circuit according to claim 1, wherein

said control means provided to control said main switching elements, said load switching element and said first and second capacitor switching elements, and

wherein said switching elements are controlled such that said first and said second capacitors (Ca, Cb) remain essentially charged to different voltage levels.

7. Circuit according to claim 5, wherein

said switching elements are controlled according to a required load output voltage level such that if a first output voltage level is required, said first capacitor switching element is activated such that said first capacitor (Ca) is connected in parallel to said load output, and if a second output voltage level is required, said second capacitor switching element is activated such that said second capacitor (Cb) is connected in parallel to said load output.

8. Power supply circuit comprising:

a main power supply unit comprising a voltage input at least one main switching element, and at least one reactive element, wherein said main switching element is controllable to deliver an output voltage (V_out) or current (I_out),

a plurality of output units connected to said main power supply unit, wherein said output units each comprise;

a load output,

a load switching element connected to said load output to connect or disconnect said main power supply unit to or from said load output,

a switched capacitor unit connected to said load output comprising a capacitor (C) and a capacitor switching element, and

a control means to control said load switching elements and said capacitor switching elements such that in each output unit said load switching element is controlled synchronously with said capacitor switching element.

9-10. -10. (canceled)