| 摘要 |
PROBLEM TO BE SOLVED: To provide an analog LSI which is provided with an open-drain type output and a bias adjustment circuit corresponding thereto, and to provide its adjustment method. SOLUTION: An internal node N on the output side of an analog circuit 12 is connected with a gate of PMOS 19 as an open-drain type output and a bias adjustment circuit 30 which can adjust a bias current in accordance with the number of cuts in a fuse 32<SB>i</SB>. A plurality of analog LSIs 10<SB>j</SB>which are manufactured at different threshold voltages for trial production are used to investigate in advance the relationship between a voltage V<SB>j</SB>when a constant current Ic is applied to an input terminal 11 and the number of cuts in the fuse to apply an optimal current to the output part of the analog LSI 10<SB>j</SB>. The constant current Ic is applied to the input terminal 11 of the analog LSI 10 to be adjusted and a voltage Vx is measured. Then, the number of cuts in the fuse corresponding to the voltage Vx is obtained, and the fuse 32<SB>i</SB>in the bias adjustment circuit 30 is cut by the obtained number. COPYRIGHT: (C)2007,JPO&INPIT
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