发明名称 |
Test mode activation by phase comparison |
摘要 |
A semiconductor integrated circuit device (10) has a pair of oscillator terminals (X0, X1) that is respectively provided with two oscillation signals having phases opposite to each other. An oscillator circuit (11) provides an internal circuit with a system clock signal based on the oscillation signals. A mode detection circuit (12) detects that the pair of oscillator terminals is respectively provided with two input signals having the same phase, and provides a test circuit (13) with a detection signal. The test circuit sets a test mode according to the detection signal, and provides the internal circuit with a predetermined test signal. By setting the test mode using a pair of external terminals, an increase in the number of external terminals of the semiconductor integrated circuit device can be prevented. <IMAGE>
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申请公布号 |
EP1557682(A1) |
申请公布日期 |
2005.07.27 |
申请号 |
EP20040014038 |
申请日期 |
2004.06.16 |
申请人 |
FUJITSU LIMITED |
发明人 |
SAITOU, TERUHIKO;OGASAWARA, AKIHIRO;SENGOKU, ATSUHIRO |
分类号 |
G01R31/28;G01R31/26;G01R31/317;H01L21/822;H01L27/04;H03B5/32;H03B5/36;(IPC1-7):G01R31/317 |
主分类号 |
G01R31/28 |
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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