Abstract: An output driver circuit for a semiconductor device. In one embodiment, the output driver is coupled to an output terminal of the semiconductor device and consists of an N-channel pull-down transistor and a P-channel pull-up transistor formed in an N-well in a P-type substrate. A tie-down region formed in the N-well is selectively coupled to a supply potential by means of a decoupling transistor, and during normal operation of the driver maintains the supply voltage bias of the N-well. An overdrive detection circuit is coupled to the output terminal. Upon detection of an overdrive condition on the output terminal, such as a voltage exceeding a predetermined maximum, or excessive current injected into the output terminal (or both), the overdrive detection circuit deasserts a control signal applied to the gate of the decoupling transistor, thereby decoupling the N-well from the supply potential. In one embodiment, the decoupling transistor is not coupled to the output terminal.

Abstract: An output driver circuit for a semiconductor device. In one embodiment, the output driver is coupled to an output terminal of the semiconductor device and consists of an N-channel pull-down transistor and a P-channel pull-up transistor formed in an N-well in a P-type substrate. A tie-down region formed in the N-well is selectively coupled to a supply potential by means of a decoupling transistor, and during normal operation of the driver maintains the supply voltage bias of the N-well. An overdrive detection circuit is coupled to the output terminal. Upon detection of an overdrive condition on the output terminal, such as a voltage exceeding a predetermined maximum, or excessive current injected into the output terminal (or both), the overdrive detection circuit deasserts a control signal applied to the gate of the decoupling transistor, thereby decoupling the N-well from the supply potential. In one embodiment, the decoupling transistor is not coupled to the output terminal.

Abstract: The invention comprises a semiconductor device with protection circuitry and a method of protecting an integrated circuit from electrostatic discharge. One aspect of the invention is a semiconductor device with protection circuitry which comprises an integrated circuit having at least one bond pad. A protection circuit is electrically connected to the bond pad and is operable to prevent damage to the integrated circuit during an electrostatic discharge event. The protection circuit comprises a first MOSFET having a first gate electrode connected in series with a second MOSFET having a second gate electrode wherein the first gate electrode and second gate electrode are commonly controlled in response to an electrostatic discharge event.

Abstract: A structure is designed with a lightly doped substrate (316) having a first conductivity type and a face. A first lightly doped region (314) has a second conductivity type and is formed within the lightly doped substrate. A first heavily doped region (308) has the first conductivity type and is formed at the face and extends to a first depth within the first lightly doped region. A second heavily doped region (312) has the second conductivity type and is formed at the face abutting the first heavily doped region. The second heavily doped region extends to a second depth and is at least partly within the first lightly doped region. A first isolation region (304) is formed at the face, abutting at least one of the first and second heavily doped regions. The first isolation region extends to a third depth that is greater than either of the first and the second depths.

Abstract: An integrated circuit includes a voltage supply internal to the integrated circuit and circuitry for sensing the voltage level of the internal voltage supply, the circuitry responsive to produce a flag signal, VPUEN, that is in a first logical state when the voltage level is below the desired level and in a second logical state when the voltage level is above the desired level. The integrated circuit also includes a buffer driver 406 having an input terminal and an output terminal, the input terminal being coupled to the circuitry for sensing the voltage level of the internal voltage supply. The operation of the circuit is such that the output terminal 400 of the buffer driver is in a high-impedance state when the flag signal is in the first logical state, and is responsive to data signals on the input terminal to produce corresponding output signals at the output terminal when the flag signal is in the second logical state.

Abstract: A DRAM output protection circuit (100). A dummy NMOS transistor (116) is connected in parallel with the NMOS output transistor (102). The gate of the dummy transistor (116) is connected through a resistor (122) to ground (108). The resistor 122 value and the gate capacitance (121,127) of the dummy transistor (116) are adjusted to achieve the desired gate matching between the dummy transistor gate (120) and the NMOS output transistor gate (110).

Abstract: An embodiment of the instant invention is an ESD protection circuit (100) for protecting a circuit from negative stress, the ESD protection circuit comprising: a first terminal (102); a second terminal (104), the circuit to be protected connected between the first and the second terminals; a substrate (202) of a first conductivity type; a first doped region (206) of a second conductivity type opposite the first conductivity type and formed in the substrate, the first doped region forming the source of a transistor; a second doped region (208) of the second conductivity and formed in the substrate spaced from the first doped region by a channel region, the second doped region forming the drain of the transistor; a first diode region (210) of the first conductivity type and formed in the substrate, the first diode region being spaced a minimum distance from the second doped region and wherein the first diode region forms the anode of a diode (108) and the second doped region forms the cathode of the diode; and