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:
Mar. 23, 1999
Filed:
Nov. 07, 1997
Joo Sun Choi, Ichon, KR;
Hyundai Electronics Industries Co., Ltd., Ichon, KR;
Abstract
A composite mode substrate voltage generation circuit for a DRAM which has a memory cell block and a peripheral circuit block formed on a single substrate. The circuit comprises a back-bias voltage generator for generating a first back-bias voltage in response to a normal refresh mode control signal or a second back-bias voltage in response to a self-refresh mode control signal and supplying the generated first or second back-bias voltage to the memory cell and peripheral circuit blocks, a first voltage level detector for detecting a level of the first back-bias voltage from the back-bias voltage generator, comparing the detected level of the first back-bias voltage with a first reference voltage level and controlling a voltage pumping operation of the back-bias voltage generator in accordance with the compared result, and a second voltage level detector for detecting a level of the second back-bias voltage from the back-bias voltage generator, comparing the detected level of the second back-bias voltage with a second reference voltage level and controlling the voltage pumping operation of the back-bias voltage generator in accordance with the compared result. A self-refresh operation can stably be performed at low power consumption, resulting in an increase in refresh efficiency of the DRAM.