Voltage generating apparatus, current generating apparatus, and test apparatus
View Patent ↗There is provided a voltage generating apparatus that outputs a power source voltage from a voltage outputting terminal. The apparatus includes a voltage outputting section that outputs the power source voltage according to a current or voltage to be input, a first differential amplification section that compares the power source voltage and a preset first reference voltage to output a first control current or voltage reducing the power source voltage output from the voltage outputting section when the power source voltage is larger than the first reference voltage and output the first control current or voltage raising the power source voltage output from the voltage outputting section when the power source voltage is smaller than the first reference voltage, a current detector that detects a detecting voltage according to a power source current output from the voltage outputting terminal, a second differential amplification section that compares the detecting voltage detected from the current detector and a second reference voltage to output a second control current or voltage reducing the power source voltage when a value obtained by subtracting the second reference voltage from the detecting voltage is larger, an addition section that inputs a current or voltage obtained by adding the first control current or voltage and the second control current or voltage into the voltage outputting section, and a third differential amplification section that supplies a voltage obtained by amplifying a difference voltage obtained by subtracting the detecting voltage from a preset third reference voltage to the second differential amplification section as the second reference voltage.
1. A voltage generating apparatus that outputs a power source voltage from a voltage outputting terminal, comprising:
a voltage outputting section that outputs the power source voltage according to a current or voltage to be input;
a first differential amplification section that compares the power source voltage and a preset first reference voltage to output a first control current or voltage reducing the power source voltage output from said voltage outputting section when the power source voltage is larger than the first reference voltage and output the first control current or voltage raising the power source voltage output from said voltage outputting section when the power source voltage is smaller than the first reference voltage;
a current detector that detects a detecting voltage according to a power source current output from the voltage outputting terminal;
a second differential amplification section that compares the detecting voltage detected from said current detector and a second reference voltage to output a second control current or voltage reducing the power source voltage when a value obtained by subtracting the second reference voltage from the detecting voltage is larger;
an addition section that inputs a current or voltage obtained by adding the first control current or voltage and the second control current or voltage into said voltage outputting section; and
a third differential amplification section that supplies a voltage obtained by amplifying a difference voltage obtained by subtracting the detecting voltage from a preset third reference voltage to said second differential amplification section as the second reference voltage.
2. The voltage generating apparatus as claimed in claim 1 , wherein said current detector comprises:
a series resistor that is provided on electric wiring between an output of said voltage outputting section and the voltage outputting terminal; and
a differential amplifier that detects the power source current by outputting a detecting voltage according to a potential difference between both ends of the series resistor.
3. A test apparatus that tests a device under test, comprising:
a voltage generating apparatus that outputs a power source voltage to be supplied to the device under test from a voltage outputting terminal; and
a test processing section that tests the device under test in a state that said voltage generating apparatus has supplied the power source voltage to the device under test, wherein
said voltage generating apparatus comprises:
a voltage outputting section that outputs the power source voltage according to a current or voltage to be input;
a first differential amplification section that compares the power source voltage and a preset first reference voltage to output a first control current or voltage reducing the power source voltage output from said voltage outputting section when the power source voltage is larger than the first reference voltage and output the first control current or voltage raising the power source voltage output from said voltage outputting section when the power source voltage is smaller than the first reference voltage;
a current detector that detects a detecting voltage according to a power source current output from the voltage outputting terminal;
a second differential amplification section that compares the detecting voltage detected from said current detector and a second reference voltage to output a second control current or voltage reducing the power source voltage when a value obtained by subtracting the second reference voltage from the detecting voltage is larger;
an addition section that inputs a current or voltage obtained by adding the first control current or voltage and the second control current or voltage into said voltage outputting section; and
a third differential amplification section that supplies a voltage obtained by amplifying a difference voltage obtained by subtracting the detecting voltage from a preset third reference voltage to said second differential amplification section as the second reference voltage.
4. The voltage generating apparatus as claimed in claim 1 , wherein said third differential amplification section reduces an amplification degree in a high-frequency area and increases an amplification degree in a low-frequency area.