Title:
MULTIPLE-VALUE VOLTAGE HIGH-SPEED COMPARATOR
Document Type and Number:
Japanese Patent JP3178563
Kind Code:
B2
Abstract:
PURPOSE: To improve comparison accuracy by making a differential detector absorb the bias current of a comparator for preventing an error voltage from being generated.
CONSTITUTION: A multiple-value measurement voltage VXi input from a device 2 to be tested is compared with a multiple-value reference voltage VSi by a low-output impedance differential detector 9, the difference δi is detected and is input to a window comparator 13, and then it is compared with a second comparison voltage VH which is larger than a first comparison voltage VL and a first comparison voltage VL. A control circuit 7 controls switching of the multiple-value measurement voltage VXi of the device 2 to be tested and at the same time supplies m-bit data Ni (bi1, bi2...bim) corresponding to a reference voltage VSi in synchronization with the switching timing. Input data Ni are D/A converted by a D/A converter 10 and are fed to a differential detector 9 as the reference voltage VSi. A buffer amplifier 12 with a high input impedance may be inserted to the input terminal of the differential detector 9.
Inventors:
Kunio Takeuchi
Application Number:
JP2275493A
Publication Date:
June 18, 2001
Filing Date:
February 10, 1993
Export Citation:
Assignee:
Advantest Corporation
International Classes:
G01R31/28; (IPC1-7): G01R31/28
Domestic Patent References:
| JP5518762A | ||||
| JP1200715A |
Attorney, Agent or Firm:
Kusano Taku (1 person outside)
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