Precision Bipolar Ramp Generator for Motor Control
Original Publication Date: 1982-Jun-01
Included in the Prior Art Database: 2005-Feb-09
The reference generator used in closed-loop, high-gain motor control systems requires voltages to linearly ramp and then hold at some fixed value. While voltage ramping is straightforward, ramping and holding at a selectable, fixed value requires more sophistication. In this system the hold voltage must be stable and not sag during long hold periods. In addition, the ramp must be very linear with the knee of the curve sharp and distinct. Fig. 1 shows the waveform of a typical output waveform illustrating the requirements, and Fig. 2 shows a block diagram of the generator system.