The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 05, 1997
Filed:
May. 26, 1995
Toshiaki Awaji, Gyoda, JP;
Masakazu Ando, Gyoda, JP;
Advantest Corporation, Tokyo, JP;
Abstract
A driver circuit for a semiconductor test system that can reduce power consumption significantly, set the power-supply voltage to low level, and can facilitate mearsurments against temperature increases. The invention is able to respond to higher amplitudes and high speeds in the semiconductor test system. The driver circuit provides an output for a semiconductor test system by switching the high and low voltage levels, and configuring a current-source device 703 to supply an output current at a period set by a switch. The invention also comprises a driver circuit that consumes less power by adapting a circuit that drastically reduces current consumption during no-load operation. To accomplish this, after receiving the positive differential-switching signal and negative differential-switching signal, the analog-voltage signal is supplied to an output-stage transistor by switching diode bridges. Output is provided by buffering and amplifying by means of forming a current mirror. Furthermore, the invention provides a driver circuit that reduces I/O spikes during the driver-inhibit mode. To achieve this, the high-level input-voltage VH is applied to the first switch terminal and the base-voltage VA of the first voltage-output device is applied to the second switch terminal. The control-current signal for the first current-source device is connected to the input terminal. This features prohibits the first current-source device from turning on until the voltage VA coincides with the high-level input-voltage VH. The same arrangement is made for the low-level side.