| 摘要 |
A voltage regulator comprises a switching stage for generating an output voltage controlled by a feedback path in which a feedback signal in the feedback path is ramp-compensated, the compensation ramp being generated from an output of the switching stage. The compensation ramp may be applied to a representation of current flowing in the output stage obtained by measuring a voltage across a capacitor 102 in series with a resistor 100, both connected in parallel with an inductor 10. A slope signal may be generated by switched capacitor 110 in series with the output voltage and resistor 112 and compared with the representative output current in comparator 104 to generate the feedback signal, which can be applied in comparator 96 to a voltage feedback signal, to thereby control the switching stage. The regulator may be a buck or boost regulator and be used to power a power amplifier (fig 10, 152), the output voltage being regulated according to the voltage across a capacitor (fig 10, 162) in series between the regulated output and the output of a linear amplifier (fig 10, 161) which receives a tracking envelope of a signal to be amplified. |
