公开(公告)号：US09983068B2

公开(公告)日：2018-05-29

申请号：US14969653

申请日：2015-12-15

Applicant: Seiko Instruments Inc.

Inventor： Masakazu Sugiura ,  Hideyuki Sawai

IPC: G01K7/00 ,  G01K15/00 ,  G01K7/01 ,  G01K3/00

CPC classification number: G01K7/01 ,  G01K3/005

Abstract: Provided is an overheat detection circuit that is capable of quickly outputting an overheated state detection signal in an overheated state without outputting an unintended erroneous output caused by disturbance noise, such as momentary voltage fluctuations in the power supply. The overheat detection circuit includes: a temperature sensor; a comparison section; and a disturbance noise removal section configured to output an overheated state detection signal to an output section after a predetermined delay time has elapsed. The delay time is reduced in proportion to temperature.

公开(公告)号：US09983067B2

公开(公告)日：2018-05-29

申请号：US14692883

申请日：2015-04-22

Applicant: Seiko Instruments Inc.

Inventor： Masakazu Sugiura ,  Tsutomu Tomioka ,  Hideyuki Sawai ,  Atsushi Igarashi ,  Nao Otsuka ,  Daisuke Okano

IPC: G01K7/01 ,  G01K3/00 ,  H01L27/02

CPC classification number: G01K7/01 ,  G01K3/005 ,  H01L27/0255

Abstract: Provided is an overheat detection circuit configured to accurately detect a temperature of a semiconductor device even at high temperature and thus avoid outputting an erroneous detection result. The overheat detection circuit includes: a PN junction element, being a temperature sensitive element; a constant current circuit configured to supply the PN junction element with a bias current; a comparator configured to compare a voltage generated at the PN junction element and a reference voltage; a second PN junction element configured to cause a leakage current to flow through a reference voltage circuit at high temperature; and a third PN junction element configured to bypass a leakage current of the constant current circuit at the high temperature.