Abstract: An inverter apparatus has an adaptable high-resolution voltage-to-frequency (V/f) control. The inverter apparatus receives an analog input signal and includes a first circuit, a second circuit, a third circuit, and a micro-controller unit. The first circuit processes a small-signal portion of the analog input signal with a larger voltage gain. The second and the third circuit both processes large-signal portions of the analog input signal with smaller voltage gains respectively. The three processed analog input signals of the first, the second, and the third circuits are converted into three digital output values respectively. The largest digital output value is selected by the micro-controller unit and supplied to a frequency operation unit for generating a corresponding output frequency.

Abstract: An inverter apparatus has an adaptable high-resolution voltage-to-frequency (V/f) control. The inverter apparatus receives an analog input signal and includes a first circuit, a second circuit, a third circuit, and a micro-controller unit. The first circuit processes a small-signal portion of the analog input signal with a larger voltage gain. The second and the third circuit both processes large-signal portions of the analog input signal with smaller voltage gains respectively. The three processed analog input signals of the first, the second, and the third circuits are converted into three digital output values respectively. The largest digital output value is selected by the micro-controller unit and supplied to a frequency operation unit for generating a corresponding output frequency.

Abstract: An Inverter system includes a comparator unit compares an analog input voltage with at least one voltage threshold to judge a voltage range for the input voltage. A DC-offset unit determines a DC-offset value to limit the input voltage within a predetermined bound. The input voltage is level-shifted and amplified by a non-inverting adder unit according to the DC-offset value and a fixed gain, and then processed by an analog to digital converter (ADC) to obtain a digital count value. A microcontroller unit calculates an original value for the input analog voltage according to the voltage range and the digital count value. When the analog input voltage could be negative value, a full-wave rectifier unit and a polarity judgment unit are used to find an absolute value and a polarity of the analog input voltage for further processing.

Abstract: An inverter system includes a comparator unit receiving an analog input voltage signal and compared with at least one threshold voltage value to determine a voltage range of the analog input voltage signal. An amplifier unit receives and amplifies the analog input voltage signal. A feedback-controlling gain unit adjusts a voltage gain of the amplifier unit according to the voltage range of the analog input voltage signal. An analog-to-digital converter unit converts an analog signal outputted from the amplifier unit into a digital count. A microcontroller unit is electrically connected with the analog-to-digital converter unit and the comparator unit. The microcontroller unit receives an indicating signal outputted from the comparator unit to know the voltage range of the analog input voltage signal. The microcontroller unit receives a digital count outputted from the analog-to-digital converter unit to correctly calculate an original value of the analog input voltage signal.