| 摘要 |
A DC control voltage being supplied to a pulse-width modulator in a switched resistor regulator control feedback loop is modified by addition of an AC offset voltage dither signal; the sum of the DC and AC voltages suffices to "turn on" the pulse-width modulator in some, but not all, of the periods of the output pulse train of the pulse-width modulator. The output pulse train controls the switch in a switched resistor regulator to turn on for a minimum period of time in some, but not all, of the periods of switching the resistor into and out of electrical connection. Thus the switched resistor regulator obtains an average duty cycle which is substantially less than the duty cycle which could be obtained with the minimum pulse width. In an alternate embodiment, a switched resistor regulator is controlled by a plurality of switches (e.g. a pair of switches whose periods of switching the resistor into and out of electrical connection are phase offset) whose minimum "turn on" voltage is staggered with respect to each other. Thus the minimum change in pulse width of the output pulse train of the pulse-width modulator is reduced, and the effective discontinuity in changes of pulse width output due to changes of the control voltage is reduced in slope.
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