| 摘要 |
The invention relates to a circuit arrangement for generating a pulse-width-modulated voltage Up having a mean value varying in the form of a sawtooth. To create such a circuit which is distinguished by much less circuit complexity than the known circuit arrangements and, nevertheless, is at least equivalent to the latter in functional respects, a step generator for generating a current IH having at least approximately hyperboloid amplitude characteristics within the individual sawtooth intervals (Ts) is provided. Furthermore, an integrator (17-19) fed with the current (IH) and integrating this current, a device (20-22) for resetting the integrator (17-19) to zero a number of times within each sawtooth interval (Ts) and a comparator circuit (23, 24, 26), which compares the output signal (Ul) of the integrator (17-19) with a direct voltage (UV) in such a manner that the output signal (Up) of the comparator (23, 24, 26) represents the pulse-width-modulated signal with sawtooth-shaped mean value, are provided. <IMAGE>
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