Electronic Control

Linear regulators are easy to implement and have better noise and drift characteristics than switching approaches. Their largest disadvantage is inefficiency: excess energy dissipated as heat. Several well-known techniques are available to minimize the input-to-output voltage across a linear regulator. I had been looking for an inexpensive, easy-to-implement, and efficient preregulator to reduce the dropout [...]

The simple circuit design in Figure 1 lets you measure all components of a current flowing in a dc servo motor. The rectified output of the circuit uses ground as a reference, so you can measure the output by using a single-ended A/D converter. The current-sense resistor, R1, has a value of 0.1Ω. The Zetex [...]

This circuit (figure 1) will impose a maximum slew rate on a signal; positive and negative rates can be independently controlled. The circuit is useful in servo applications where the error signal needs to be limited to be within the power rails to ensure predictable operation.
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