Electronic digital logic circuitry – Signal sensitivity or transmission integrity – Output switching noise reduction
Patent
1995-08-21
1997-05-13
Westin, Edward P.
Electronic digital logic circuitry
Signal sensitivity or transmission integrity
Output switching noise reduction
326 58, 326 83, H03K 190185
Patent
active
056296347
ABSTRACT:
An output driver circuit for a semiconductor chip has a push-pull output with a P-channel pull-up and an N-channel pull-down. Predrivers produce push-pull outputs for driving the gates of the output driver. Compensator circuits, one for the N-channel pull-down, and one for the P-channel pull-up, are used to prevent the transition from high-to-low or low-to-high from being too rapid, which could cause noise due to inductance of the package leads. A feedback circuit halts the operation of the compensator circuits after a short interval. An overvoltage circuit formed in a well of the semiconductor chip holding the driver circuit, having an input coupled to receive the data output of the predriver circuit going to the P-channel pull-up, also functions to prevent damage to the output driver circuit due to overvoltage on the output node. A stack of diodes connected in a forward direction between the N-well of the P-channel pull-up transistor and the positive terminal of the voltage supply serves to clamp the output node if it tends to go above a selected overvoltge level.
REFERENCES:
patent: 4477741 (1984-10-01), Moser, Jr.
patent: 4612466 (1986-09-01), Stewart
patent: 4782250 (1988-11-01), Adams et al.
patent: 4825099 (1989-04-01), Barton
patent: 4952818 (1990-08-01), Erdelyi et al.
patent: 4963766 (1990-10-01), Lundberg
patent: 4975598 (1990-12-01), Borkar
patent: 5017807 (1991-05-01), Kriz
patent: 5021684 (1991-06-01), Ahuja
patent: 5117129 (1992-05-01), Hoffman
patent: 5179299 (1993-01-01), Tipon
patent: 5206544 (1993-04-01), Chen et al.
patent: 5212801 (1993-05-01), Farmer
patent: 5243571 (1993-09-01), Brossard
patent: 5280204 (1994-01-01), Livolsi
patent: 5321319 (1994-06-01), Mahmood
patent: 5331228 (1994-07-01), Brady
patent: 5332932 (1994-07-01), Runaldue
patent: 5394363 (1995-02-01), Han
patent: 5396128 (1995-03-01), Dunning et al.
patent: 5399925 (1995-03-01), Nguyen
patent: 5408146 (1995-04-01), Nguyen et al.
patent: 5430387 (1995-07-01), Bechade
patent: 5444397 (1995-08-01), Wong
patent: 5450025 (1995-09-01), Shay
patent: 5467031 (1995-11-01), Nguyen
Carl Allen R.
Piro Ronald A.
Driscoll Benjamin D.
International Business Machines - Corporation
Walsh Robert
Westin Edward P.
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