发明名称 |
Variable voltage threshold ESD protection |
摘要 |
An ESD protective circuit is described which has a very low, variable turn-on threshold by using a shunting MOSFET which has an isolated substrate/body which is connected to an electrode that is provided in addition to the gate, source and drain electrodes. A variable gate voltage which is preferably a function of an ESD voltage is used to trigger the MOSFET into conduction. A voltage is applied to the substrate/body of the MOSFET to lower the turn-on voltage. The voltage on the substrate allows the turn-on voltage to be adjusted for different applications and/or to be adjusted dynamically to respond to events. The substrate voltage is also preferably derived from the ESD voltage. Preferably the MOSFET has an epitaxial region with an electrode and a subcollector with an electrode. The epitaxial region electrode can be connected to the gate to improve the turn-on performance. The subcollector electrode can be connected to the substrate/body electrode to contribute to lowering the turn-on voltage. A preferred embodiment uses an ESD protective device according to the invention to protect a magnetic transducer in a data storage system.
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申请公布号 |
US6552879(B2) |
申请公布日期 |
2003.04.22 |
申请号 |
US20010768631 |
申请日期 |
2001.01.23 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
VOLDMAN STEVEN HOWARD |
分类号 |
G11B5/31;G11B5/39;G11B5/40;(IPC1-7):G11B5/139 |
主分类号 |
G11B5/31 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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