发明名称 |
Read only memory circuit |
摘要 |
A ROM circuit is used in place of a conventional fuse type ROM which is incorporated in a semiconductor integrated circuit network together with other circuit blocks on a chip. The ROM circuit comprises a first transistor having a control and a floating gate and a depletion type second transistor having a gate formed as an extension of the floating gate. The second transistor outputs a high level control signal if hot electrons have been accumulated on the floating gate of the first transistor by the application of a predetermined high level input signal to the control gate thereof, and outputs a low level signal when the high level input signal has not been provided to the control gate. The first transistor is freed from a soft write problem because it is separated from a voltage source in the read mode.
|
申请公布号 |
US4725980(A) |
申请公布日期 |
1988.02.16 |
申请号 |
US19850798782 |
申请日期 |
1985.11.18 |
申请人 |
FUJITSU LIMITED |
发明人 |
WAKIMOTO, HIDEYUKI;YOSHIDA, MASANOBU |
分类号 |
G11C17/00;G11C16/04;G11C16/06;G11C29/00;G11C29/04;H01L21/8247;H01L27/10;H01L29/788;H01L29/792;(IPC1-7):H01L29/78;G11C11/34;H03K5/13 |
主分类号 |
G11C17/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|