Voltage controller for a pulsed load, in particular for a mobile-telephone or telematics transmitter

• US 20020072399A1
• Filed: 11/20/2001
• Published: 06/13/2002
• Est. Priority Date: 11/20/2000
• Status: Abandoned Application

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Fritz, Werner
• Application Number:
  US09/988,581
• Publication Number:
  US 20020072399A1
• Time in Patent Office: Days
• US Class Current: 455/572
• CPC Class Codes: G05F 1/575 characterised by the feedback circuit
• CPC Class Codes: H02M 1/0025 Arrangements for modifying reference values, feedback values or error values in the control loop of a converter

Abstract

The present invention relates to a voltage controller for a pulsed load, in particular for a mobile-telephone or telematics transmitter. In order to prevent phase errors and frequency errors resulting from these which arise when in the event of falling voltage the current for a pulsed load (14), in particular for a mobile-telephone or telematics transmitter transmitting in burst mode, is increased and in order to keep the power of the load (14), in particular the transmission power, constant the voltage controller (15) according to the invention comprises a control element (21) which is connected between an input connection (22) for the application of an input voltage (Vin) and an output connection (23) for supplying an output voltage (Vout) to a pulsed load (14), a comparison element (24) which compares an actual value signal (Vo) corresponding to the output voltage (Vout) with a desired value signal (Vref) and supplies a control signal (Vc) to the control element (21) in order to influence the output voltage (Vout) to the effect of adapting the actual value signal (Vo) to the desired value signal (Vref), and a desired value circuit (26) which derives the desired value signal (Vref) from the input voltage (Vin) in such a way that it is substantially constant over the duration of a load pulse.

Claims

1. Voltage controller for a pulsed load, in particular for a mobile-telephone or telematics transmitter having

a control element (21) which is connected between an input connection (22) for the application of an input voltage (Vin) and an output connection (23) for supplying an output voltage (Vout) to a pulsed load (14),

a comparison element (24) which compares an actual value signal (Vo) corresponding to the output voltage (Vout) with a desired value signal (Vref) and supplies a control signal (Vc) to the control element (21) in order to influence the output voltage (Vout) to the effect of adapting the actual value signal (Vo) to the desired value signal (Vref), and

a desired value circuit (26, 26′

) which derives the desired value signal (Vref) from the input voltage (Vin) in such a way that it is substantially constant over the duration of a load pulse.

2. Voltage controller according to claim 1, characterised in that the desired value circuit (26, 26′

) contains a hold-delay element (30, 33;

34) which at its output supplies an output signal corresponding to the input voltage (Vin) as the desired value signal (Vref).

3. Voltage controller according to claim 2, characterised in that a lowpass (30, 33) is provided as the hold-delay element.

4. Voltage controller according to claim 3, characterised in that the time constant of the lowpass (30, 33) is a multiple of the duration of a load pulse.

5. Voltage controller according to claim 2, characterised in that for the hold-delay element a sample-and-hold element (34) is provided whose hold time corresponds at least to the duration of a load pulse.

6. Voltage controller according to claim 5, characterised in that a sampling command signal for the sample-and-hold element (34) is derived from a load pulse control signal in such a way that the output signal (Vref) of the sample-and-hold element (34) corresponds to the input voltage (Vin) applied shortly before a load pulse.

7. Voltage controller according to claim 5 or 6, characterised in that the desired value circuit (26′

) has as smoothing element a lowpass (30, 33) whose output signal is sampled in order to construct the desired value signal (Vref).

8. Voltage controller according to one of the preceding claims, characterised in that the desired value circuit (26, 26′

) has a voltage divider (33) on which the desired value signal (Vref) can be tapped off.

9. Voltage controller according to one of the preceding claims, characterised in that an actual value capture circuit (25) is provided which has a voltage divider (25′

) on which an actual value signal (Vo) corresponding to the output voltage (Vout) can be tapped off.

10. Voltage controller according to one of the preceding claims, characterised in that a voltage limiting circuit (29) is connected to the input of the desired value circuit (26, 26′

) in order to fix a maximum value for the desired value signal (Vref).

11. Voltage controller according to one of the preceding claims, characterised in that a reference voltage signal (Vmin) is connected to the desired value circuit (26, 26′

) in order to fix a minimum value for the desired value signal (Vref).