Power supply voltage generator

• US 6,448,751 B1
• Filed: 10/27/2000
• Issued: 09/10/2002
• Est. Priority Date: 10/28/1999
• Status: Expired due to Term

• Current Assignee: Callahan Cellular LLC (Intellectual Ventures LLC)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Becker, Rolf Friedrich Philipp
• Primary Examiner(s): BERHANE, ADOLF D
• Application Number:
  US09/698,770
• Time in Patent Office: 683 Days
• Field of Search: 323/282, 323/283, 323/284, 323/351
• US Class Current: 323/284
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence

Abstract

This invention concerns a power supply voltage generator (1) for providing a second supply voltage (V_DD2) for an electronic circuitry (60). A voltage converter (50) receives a first supply voltage (V_DD1), and converts this into said second supply voltage (V_DD2), such that its output voltage (V_DD2) fluctuates in a control range between a lower limit (V_LOW) and an upper limit (V_HIGH). A voltage parameter source circuitry (3) generates a voltage parameter signal (V_LOW) which is substantially equal to the minimum supply voltage value (V_min) of the electronic circuitry (60), and feeds this voltage parameter signal (V_LOW) to a parameter input (53) of the converter (50). The voltage parameter source circuitry (3) comprises a VCO (10) incorporated in a PLL. The voltage parameter signal (V_LOW) is derived from a control signal (V_contr) for the VCO (10).

Claims

1. Power supply voltage generator (1) comprising a controllable voltage converter (50), with a primary voltage input (51) for receiving a first supply voltage (V_DD1), and a secondary voltage output (52) for delivering a second supply voltage (V_DD2);

the voltage converter (50) being arranged to control the level of its output voltage (VDD₂) within a range between a lower limit (V_LOW) and an upper limit (V_HIGH);

the voltage converter (50) further comprising a parameter input (53) for receiving an input parameter control signal that indicates a suitable value for said lower limit (V_LOW).

2. Power supply voltage generator (1) for providing a second supply voltage (V_DD2) for an electronic circuitry (60), comprising:

a controllable voltage converter (50);

a voltage parameter source circuitry (3) for generating a voltage parameter signal (V_LOW) which is substantially equal to a minimum supply voltage value (V_min) of the electronic circuitry (60); and

wherein the voltage parameter source circuitry (3) has an output (2) provided as a parameter input (53) to the voltage converter (50).

3. Power supply voltage generator (1) according to claim 2, wherein the voltage parameter source circuitry (3) is designed such that the characteristics of its output signal match substantially the characteristics of V_min of the electronic circuitry (60).

4. Power supply voltage generator (1) according to claim 2, wherein the voltage parameter source circuitry (3) comprises a voltage controlled oscillator (VCO) (10) which is controlled to generate a constant frequency, wherein the VCO (10) is implemented in a same chip as the electronic circuitry (60), and wherein the control parameter (V_LOW) is derived from the control voltage to the VCO.

5. Power supply voltage generator (1) according to claim 4, wherein said VCO (10) is incorporated in a phase locked loop (PLL) for controlling the VCO (10).

6. Power supply voltage generator (1) according to claim 5, wherein the VCO (10) provides a VCO-signal (f_VCO);

wherein the VCO (10) is controlled by a control voltage signal (V_contr) so that said VCO-signal (f_VCO) is a substantially stable signal; and

wherein said control signal (V_LOW) is derived from said control voltage signal (V_contr).

7. Power supply voltage generator (1) according to claim 6, wherein the voltage parameter source circuitry (3) comprises an amplifier (40), receiving the control voltage signal (V_contr) at an input (41), and providing an amplified voltage signal at an output (42) as said control parameter signal (V_LOW), such that said control parameter signal (V_LOW) differs from said control voltage signal (V_contr) substantially only by a gain factor.

8. Power supply voltage generator (1) according to claim 7, wherein said gain factor of the amplifier (40) is presettable by means of software.

9. Power supply voltage generator (1) according to claim 5, wherein an output of the VCO (10) is coupled to a first input of a phase and frequency detector (30), through a divider (11);

wherein the voltage parameter source circuitry (3) further comprises an oscillator (20), comprising a quartz crystal (21), an output of which is coupled to a second input of the phase and frequency detector (30);

wherein an output signal of the phase and frequency detector (30) is applied as control signal to a charge pump (31); and

wherein an output signal of the charge pump (31), through a loop filter (32), is fed back as control signal (V_contr) to a control input of the VCO (10) for controlling the frequency of the output signal (f_VCO) of the VCO (10).