초록 ▼

A motor control circuit, including a filter amplifier which includes a clamping circuit to limit the maximum voltage of the filter amplifier. The filter amplifier is clamped to essentially the same level as the following error amplifier, which drives the power transistor which drives the motor. Thus

A motor control circuit, including a filter amplifier which includes a clamping circuit to limit the maximum voltage of the filter amplifier. The filter amplifier is clamped to essentially the same level as the following error amplifier, which drives the power transistor which drives the motor. Thus, the requisite control voltage is normally present anyway (since this voltage is used to limit the amount of maximum current in the motor). Since the corresponding level of current is selected to ensure adequate current during start up, this signal is therefore appropriate to limit the output voltage of the filter amplifier. This improvement adds very little circuit complexity, and reduces the settling time of the motor controller at startup.

대표청구항 ▼

[ What is claimed is:] [1.] A control circuit, comprising:a filter amplifier comprising a first input operatively connected to receive a command voltage and a second input operatively connected to receive a reference voltage, and further comprising one or more passive elements connected therewith;an

[ What is claimed is:] [1.] A control circuit, comprising:a filter amplifier comprising a first input operatively connected to receive a command voltage and a second input operatively connected to receive a reference voltage, and further comprising one or more passive elements connected therewith;an error amplifier, integrated with said filter amplifier, and comprising a first input operatively connected to be driven by an output of said filter amplifier, an output connectable to drive a power transistor, and a second input connectable to receive a feedback value which is proportional to the current passed by the power transistor;wherein said filter amplifier and said error amplifier each comprise:a respective output transistor of a first majority-carrier conduction type connected to drive said respective output, anda respective clamp transistor of a second majority-carrier conduction type connected to limit the voltage on a control terminal of said respective output transistor,both said clamp transistors having respective control terminals thereof connected to a respective common constant voltage to limit said outputs of respective said amplifiers when said respective amplifiers are operating.