Patent search ap:("IBM") AND inv:"TSENG SAMUEL CHIN-CHENG" Page 1

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发明专利
未知

公开(公告)号：DE2228644A1

公开(公告)日：1973-02-15

申请号：DE2228644

申请日：1972-06-13

Applicant: IBM

Inventor： ASH ERIC A , TSENG SAMUEL CHIN-CHENG

IPC: H03H9/02 , H03H9/42 , H03H9/76 , H03H9/00

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