Patent US5438545A successfully refreshed from Google Patents.
US5438545A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data output buffer of semiconductor memory device for preventing noises
Assignee: SK Hynix Inc
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Filing: 1994-02-23
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Granted: 1995-08-01
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Expires: 2014-02-23
Abstract
Abstract A data output buffer, which includes a data output driver which in turn includes a pull-up circuit (14) operating in response to a first signal and a pull-down circuit (I10) operating in response to a second signal, and a control circuit for sensing a current flowing into the pull-down circuit via a feed-back and controlling the slope of the second signal in accordance with the sensed current. The control circuit includes a sensing circuit (I13) for sensing current flowing into the pull-down circuit upon driving data, and the magnitude of noises generated at the actual ground line (GND 1 +GND 2 ) due to the current, a voltage adjustment circuit (I14) which operates in response to the output signal of the sensing circuit and thereby adjusts the gate voltage of the pull-down circuit. Thereby, the noises generated in the chip are repressed without affecting the operational speed of the chip.
Inventors
- 👤 Jae K. Sim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:58
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/02; H03K19/08; H03K19/094; H03K19/003; H03K19/00346; H03K19/00361
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
164 words
A data output buffer, comprising: a data output driver including pull-up means operable in response to a first signal and pull-down means operable in response to a second signal; control means for detecting a current flowing into said pull-down means and for controlling the slope of the second signal in accordance with the detected current; wherein said control means includes an inverter and sensing means for sensing the current flowing into said pull-down means and the magnitude of noises generated at the ground of said pull-down means; and voltage adjusting means operable in accordance with an output signal of said sensing means for adjusting a gate voltage of said pull-down means; wherein said sensing means includes (a) an N-MOS transistor which has a gate electrode for receiving an output signal of the inverter, a drain electrode connected to an output of said data output driver, and a source electrode, and (b) a current sensing resistor connected in between said source electrode and the ground.
Claim 2
Dependent Claim
164 words
A data output buffer, comprising: a data output driver including pull-up means operable in response to a first signal and pull-down means operable in response to a second signal; control means for detecting a current flowing into said pull-down means and for controlling the slope of the second signal in accordance with the detected current; wherein said control means includes an inverter and sensing means for sensing the current flowing into said pull-down means and the magnitude of noises generated at the ground of said pull-down means; and voltage adjusting means operable in accordance with an output signal of said sensing means for adjusting a gate voltage of said pull-down means; wherein said sensing means includes (a) an N-MOS transistor which has a gate electrode for receiving an output signal of the inverter, a drain electrode connected to an output of said data output driver, and a source electrode, and (b) a current sensing resistor connected in between said source electrode and the ground.
Claim 3
Dependent Claim
183 words
A data output buffer, comprising: a data output driver including pull-up means operable in response to a first signal and pull-down means operable in response to a second signal; control means for detecting a current flowing into said pull-down means and for controlling the slope of the second signal in accordance with the detected current; wherein said control means includes an inverter and sensing means for sensing the current flowing into said pull-down means and the magnitude of noises generated at the ground of said pull-down means; and voltage adjusting means operable in accordance with an output signal of said sensing means for adjusting a gate voltage of said pull-down means; wherein said voltage adjusting means includes (a) a P-MOS transistor which has a gate electrode connected to a second ground, a source electrode connected to a voltage source and a drain electrode connected to an inverter, and (b) an N-MOS transistor which has a gate electrode connected to said sensing means, a source electrode connected to a first ground, and a drain electrode connected to said drain electrode of said P-MOS transistor.
Claim 4
Dependent Claim
183 words
A data output buffer, comprising: a data output driver including pull-up means operable in response to a first signal and pull-down means operable in response to a second signal; control means for detecting a current flowing into said pull-down means and for controlling the slope of the second signal in accordance with the detected current; wherein said control means includes an inverter and sensing means for sensing the current flowing into said pull-down means and the magnitude of noises generated at the ground of said pull-down means; and voltage adjusting means operable in accordance with an output signal of said sensing means for adjusting a gate voltage of said pull-down means; wherein said voltage adjusting means includes (a) a P-MOS transistor which has a gate electrode connected to a second ground, a source electrode connected to a voltage source and a drain electrode connected to an inverter, and (b) an N-MOS transistor which has a gate electrode connected to said sensing means, a source electrode connected to a first ground, and a drain electrode connected to said drain electrode of said P-MOS transistor.
Claim 5
Dependent Claim
196 words
A data output buffer, comprising: data buffer means for buffering data signals; inversion data buffer means for buffering inversion data signals; a data output driver which includes a pull-up means operable in response to an output signal of said data buffer means and a pull-down means operable in response to an output signal of said inversion data buffer means; control means for sensing a current flowing into said pull-down means via a feed-back and controlling the output signal of said inversion data buffer means; wherein said control means includes sensing means for sensing a current flowing into said pull-down means upon driving data and the magnitude of noises generated at the ground of said pull-down means in accordance with the current; and voltage adjustment means operable in accordance with an output signal of said sensing means for adjusting the gate voltage of said pull-down means; wherein said sensing means includes an N-MOS transistor having a drain electrode connected to an output of said data output driver, a gate electrode for receiving an output signal of an inverter; and a current sensing resister connected in series between a source electrode of said N-MOS transistor and the ground.
Claim 6
Dependent Claim
196 words
A data output buffer, comprising: data buffer means for buffering data signals; inversion data buffer means for buffering inversion data signals; a data output driver which includes a pull-up means operable in response to an output signal of said data buffer means and a pull-down means operable in response to an output signal of said inversion data buffer means; control means for sensing a current flowing into said pull-down means via a feed-back and controlling the output signal of said inversion data buffer means; wherein said control means includes sensing means for sensing a current flowing into said pull-down means upon driving data and the magnitude of noises generated at the ground of said pull-down means in accordance with the current; and voltage adjustment means operable in accordance with an output signal of said sensing means for adjusting the gate voltage of said pull-down means; wherein said sensing means includes an N-MOS transistor having a drain electrode connected to an output of said data output driver, a gate electrode for receiving an output signal of an inverter; and a current sensing resister connected in series between a source electrode of said N-MOS transistor and the ground.
Claim 7
Dependent Claim
216 words
A data output buffer, comprising: data buffer means for buffering data signals; inversion data buffer means for buffering inversion data signals; a data output driver which includes a pull-up means operable in response to an output signal of said data buffer means and a pull-down means operable in response to an output signal of said inversion data buffer means; control means for sensing a current flowing into said pull-down means via a feed-back and controlling the output signal of said inversion data buffer means; wherein said control means includes sensing means for sensing a current flowing into said pull-down means upon driving data and the magnitude of noises generated at a first ground and a second ground in accordance with the current; and voltage adjusting means operable in accordance with an output signal of said sensing means for adjusting the gate voltage of said pull-down means; wherein said voltage adjusting means includes (a) a P-MOS transistor having a gate electrode connected to the second ground, a source electrode connected to a voltage source and a drain electrode connected to an inverter, and (b) an N-MOS transistor having a gate electrode connected to said sensing means, a source electrode connected to the first ground and a drain electrode connected to said drain electrode of said P-MOS transistor.
Claim 8
Dependent Claim
216 words
A data output buffer, comprising: data buffer means for buffering data signals; inversion data buffer means for buffering inversion data signals; a data output driver which includes a pull-up means operable in response to an output signal of said data buffer means and a pull-down means operable in response to an output signal of said inversion data buffer means; control means for sensing a current flowing into said pull-down means via a feed-back and controlling the output signal of said inversion data buffer means; wherein said control means includes sensing means for sensing a current flowing into said pull-down means upon driving data and the magnitude of noises generated at a first ground and a second ground in accordance with the current; and voltage adjusting means operable in accordance with an output signal of said sensing means for adjusting the gate voltage of said pull-down means; wherein said voltage adjusting means includes (a) a P-MOS transistor having a gate electrode connected to the second ground, a source electrode connected to a voltage source and a drain electrode connected to an inverter, and (b) an N-MOS transistor having a gate electrode connected to said sensing means, a source electrode connected to the first ground and a drain electrode connected to said drain electrode of said P-MOS transistor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1998-07-31 | 1999-01-30 | 1999-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-31 | 2003-01-30 | 2003-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-31 | 2007-01-30 | 2007-08-01 | $7700.00 | Window Closed / Lapsed |