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US5036227A Expired / Lapsed US ⏱️ 0.0 years remaining

Row address strobe signal input buffer for preventing latch-up

Assignee: Samsung Electronics Co Ltd
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Filing: 1990-02-27
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Granted: 1991-07-30
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Expires: 2010-02-27
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Abstract

Abstract The row address strobe signal input buffer, or "chain pre-charge" circuit, includes a pad receiving a row address strobe signal ( &upbar& R). A Schmitt trigger receives the &upbar& R signal from the pad, and is responsive to a start-up signal. A control section responds to the start-up signal and the output thereof is connected to the output of the Schmitt trigger. A NAND gate and inverters are connected to the output of the control section. A first pre-charge circuit, connected between the pad and the Schmitt trigger, prevents a floating state at the time of initial power source voltage supply. A second pre-charge circuit, connected to an input of one of the inverters which provides the output of the row address strobe signal input buffer, also helps prevent the floating state.

Inventors

  • 👤 Sooin Jo
  • 👤 Jaiwhan Yu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 13:08
CPC Classifications
G; G06; G06F; G06F1/00; H; H03; H03K; H03K17/00; H03K17/22; H03K3/00; H03K3/02; H03K3/353; H03K3/356; H03K3/3565

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 130 words
A row address strobe signal input buffer comprising: a pad receiving an input row address strobe signal; a Schmitt trigger means connected to receive said row address strobe signal from said pad, and responsive to a start-up signal; a control section responsive to said start-up signal, and connected to an output of said Schmitt trigger means; a NAND gate and inverters connected to an output of said control section; a first pre-charge means for preventing a floating state at the time of power source voltage supply, said first pre-charge means being connected between said pad and said Schmitt trigger; and a second pre-charge means for preventing a floating state connected to an input of one of said inverters which provides an output of the row address strobe signal input buffer.
Claim 2
Dependent Claim 130 words
A row address strobe signal input buffer comprising: a pad receiving an input row address strobe signal; a Schmitt trigger means connected to receive said row address strobe signal from said pad, and responsive to a start-up signal; a control section responsive to said start-up signal, and connected to an output of said Schmitt trigger means; a NAND gate and inverters connected to an output of said control section; a first pre-charge means for preventing a floating state at the time of power source voltage supply, said first pre-charge means being connected between said pad and said Schmitt trigger; and a second pre-charge means for preventing a floating state connected to an input of one of said inverters which provides an output of the row address strobe signal input buffer.
Claim 3
Dependent Claim 40 words
A buffer according to claim 1, wherein said first pre-charge means includes a MOS transistor which operates as a resistance to limit a current level between a power source voltage and said pad for receiving a row address strobe signal.
Claim 4
Dependent Claim 37 words
A buffer according to claim 1, wherein said second pre-charge means includes a MOS transistor which operates as a resistance to limit a current level between a power source voltage and said said one of said inverters.
Claim 5
Dependent Claim 30 words
A buffer according to claim 1, further comprising a third pre-charge means which operates as a resistance, said third pre-charge means being connected to one end of said NAND gate.
Claim 6
Dependent Claim 47 words
A buffer according to claim 4, wherein each of the pre-charge means comprises a MOS transistor, and the size of the MOS transistor of said first pre-charge means is larger and exhibits a larger loading capacitance than the MOS transistors of said second and third pre-charge means.

References Cited (Backward Citations)

US4636661A Cited
US4763023A Cited
US4939394A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-07-29 1995-01-28 1995-07-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-07-29 1999-01-28 1999-07-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-07-29 2003-01-28 2003-07-30 $7700.00 Window Closed / Lapsed

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