US 7,456,627 B2
Voltage generating apparatus, current generating apparatus, and test apparatus
Hiroki Andoh, Tokyo (Japan); and Hironori Tanaka, Tokyo (Japan)
Assigned to Advantest Corporation, Tokyo (Japan)
Filed on Dec. 07, 2007, as Appl. No. 11/952,668.
Application 11/952668 is a division of application No. 11/475577, filed on Jun. 27, 2006, granted, now 7,345,467.
Prior Publication US 2008/0088287 A1, Apr. 17, 2008
Int. Cl. G01R 31/28 (2006.01); G01R 31/02 (2006.01)
U.S. Cl. 324—158.1  [324/763] 3 Claims
OG exemplary drawing
 
1. A current generating apparatus that outputs a power source current from a current outputting terminal, comprising:
a current outputting section that outputs the power source current according to a current or voltage to be input;
a current detector that detects a detecting voltage according to the power source current output from the current outputting terminal;
a fourth differential amplification section that compares the detecting voltage and a fourth reference voltage according to a preset first reference current to output a first control current or voltage reducing the power source current output from said current outputting section when the power source current is larger than the first reference current and output the first control current or voltage raising the power source current output from said current outputting section when the power source current is smaller than the first reference current;
a fifth differential amplification section that compares a power source voltage at the current outputting terminal and a fifth reference voltage to output a second control current or voltage reducing the power source current when a value obtained by subtracting the fifth reference voltage from the power source 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 current outputting section; and
a sixth differential amplification section that supplies a voltage obtained by amplifying a difference voltage obtained by subtracting the power source voltage from a preset sixth reference voltage to said fifth differential amplification section as the fifth reference voltage.