Abstract: Crystal oscillator circuitry provides a very fast start-up function requiring less than 100 mS. The crystal oscillator circuitry enters a stop mode when a control signal transitions from a first logic level to a second logic level thereby causing a crystal to stop oscillating. In order to initiate the fast start-up function, a pulse is provided to the gate of a transistor which is electrically connected between a first node and a second node, thus causing the voltage of the first node to move towards the voltage level of the second node and the second node to move towards the voltage level of the first node. Upon initiation of the start-up function, the energy at the crystal of the crystal oscillator circuitry is at least four times higher than the energy required in a steady state mode. The crystal oscillator circuitry has a VT (threshold voltage) independent high feedback resistance which provides stable oscillation frequency over a wide range of Vcc supply voltage.

Abstract: A comparator with a built-in hysteresis is disclosed. The comparator has a differential input stage, an output stage, and a bias circuit with a hysteresis circuit. The hysteresis circuit selectively applies a bias voltage to the differential input stage to achieve the hysteresis.

Abstract: An output driver circuit an integrated circuit memory device prevents crowbar currents from occurring. The output driver uses just one resistive element having multiple taps so that the amount of silicon area used for slew rate control is minimized. The signals which control the output driver devices are carefully balanced for no skew and cross at a voltage level of Vcc/2 so that there is no crowbar current generated during tri-stating of the output driver output signal.

Abstract: A memory device with a sense amplifier enable line having the same resistance and capacitance as a local wordline. The sense amplifier enable line is made out of the same material, has the same layout, and has the same load placed on as a local wordline, this will make the sense amplifier enable line have the same resistance, capacitance, and load characteristics as a local wordline. The load on the sense amplifier enable line is a combination of the sense amplifier enable line operational circuitry and sense amplifier enable line load circuit.

Abstract: A semiconductor device includes an insulating support. A strip of semiconductor material has two ends in contact with the insulating support and a midsection extending between the ends. A dielectric layer encircles the midsection, and a conductive layer encircles the dielectric layer. The conductive layer has a substantially constant width such that a gate electrode formed within the conductive layer is fully self-aligned with drain and source regions formed within the ends.

Abstract: A method is provided for forming a planar transistor of a semiconductor integrated circuit, and an integrated circuit formed according to the same. A transistor encapsulated in a dielectric is formed over a substrate. First source and drain regions are formed in the substrate adjacent the transistor. Conductive raised second source and drain regions are formed which overly exposed portions of the first substrate source and drain regions adjacent the transistor. The raised second source and drain regions are formed such that an upper surface of the raised second source and drain regions are substantially planar with an upper surface of the transistor. The dielectric encapsulating the transistor electrically isolates the transistor from the raised second source and drain regions.

Abstract: According to the present invention, the data access time of a chip select condition of a synchronized memory integrated circuit device is pipelined so that it approximates the normal access time of data for the device. The response time to the chip enable signal during a deselect condition is immediate and thus is not pipelined. The access time of data due to a chip select condition is pipelined and matched with the normal access time of data propagation so that any access time pushout previously incurred when transitioning the device output signal from a high impedance (disabled) to a low impedance (enabled) state is eliminated. The circuitry of the present invention tri-states the output pin of the synchronized memory device on the initial rising edge of an external clock signal supplied to the device upon a deselect condition. Upon the first cycle of the select condition, when the external clock signal initially rises, an Output Disable Internal signal remains a high logic state.

Abstract: A high-side gate driving circuit, where a current-mode differential error amplifier is used to regulate the current sourced to the gate. A current path is provided from the gate to the source of the power device, and a constant current is provided to the gate. A variable current source is also provided, and this current source is controlled by the output of the error amplifier. Preferably a voltage offset (avalanche breakdown diode) is interposed between the gate and source of the high-side driver; this ensures that the feedback loop will operate in a bistable mode, which avoids instability problems.

Abstract: A CMOS SRAM cell in which a patterned SIMOX layer forms a buried oxide beneath the PMOS devices, but not beneath the NMOS devices. Latchup is impossible, and well diffusions are not needed.

Abstract: A control circuit for providing a stable, adjustable, time constant for use as a master time constant is presented. Used as a master time-constant circuit, this control circuit can ensure multiple slave circuits are precisely calibrated. The circuit includes a charging section that receives a series of calibrating pulses. The reference cell's voltage is compared to a reference voltage equal of Vcc/e. If the cell's voltage is below the reference voltage, a current source charges a capacitor, lowering the resistance of the transistor in the cell to correct the time circuit inaccuracy. Conversely, if the cell's voltage is above the reference voltage, a current sink discharges the capacitor, raising the transistor's resistance. This also corrects the time circuit inaccuracy. Thus, this circuit includes a method to correct time-constants which are too large or too small. This circuit is used in various applications where extreme accuracy and precision is needed, such as media drive read/write heads.

Abstract: A method and structure for self-aligned zero-margin contacts to active and poly-1, using silicon nitride (or another dielectric material with low reflectivity and etch selectivity to oxide) for an etch stop layer and also for sidewall spacers on the gate.

Abstract: A brushless DC motor system using PWM switching, in which the PWM switching is temporarily frozen whenever a zero crossing is expected in the back EMF. This avoids disruption of zero-crossing detection due to switching transients from the power transistor.

Abstract: A method is provided for forming an improved landing pad with barrier of a semiconductor integrated circuit, and an integrated circuit formed according to the same. An opening is formed through a first dielectric layer to expose a portion of a diffused region. A landing pad is formed over the first dielectric layer and in the opening. The landing pad preferably comprises a silicide layer disposed over a barrier layer which is disposed over a polysilicon layer. The landing pad will provide for smaller geometries and meet stringent design rules such as that for contact space to gate. The barrier layer, formed as part of the landing pad, will provide for a uniform and high integrity barrier layer between the diffused region and an overlying aluminum contact to prevent junction spiking. A second dielectric having an opening therethrough is formed over the landing pad. A conductive contact, such as aluminum, is formed in the contact opening.

Abstract: A current source for generating a current that is relatively stable over variations in the power supply voltage and temperature, and over variations in process parameters is disclosed. The current source includes a bias circuit, for producing a compensating bias voltage, and a current mirror. The bias circuit utilizes a voltage divider to generate a divided voltage based on the power supply value. The divided voltage is applied to the gate of a modulating transistor (biased in saturation) in a first current mirror, which controls a current applied to a linear load device. The voltage across the load device determines the bias voltage, which is in turn applied to the gate of a transistor in the reference leg of a second current mirror. The bias voltage controls the current in the reference leg of the second current mirror, and an output leg mirrors the second reference current to produce a stable output current.

Abstract: A method and a circuit for detecting zero crossing points for a brushless, sensorless, three-phase DC motor operated in a PWM mode. The circuit senses a BEMF signal in a floating coil and generates a first signal when the BEMF signal is separated from the center tap voltage by a selected offset voltage amount. The circuit overrides the PWM mode and drives a high side driving transistor to a conducting state until the zero crossing point is detected.

Abstract: An integrated circuit memory structure is disclosed where the read and write buses (true and complement) are coupled to redundant input/output select circuits through permanently programmable selection element that can disconnect the read and write busses from the redundant input/output select circuit.

Abstract: A master-slave-master latch circuit for loading data vertically or horizontally. A first master latch is coupled to an input terminal for receiving data. Under control of a clock, the data is transferred from the master latch to a slave latch input terminal. Under control of the slave latch clock, the data is shifted horizontally into the slave latch. Under control of a further horizontal shift clock the data is shifted to a further master latch. The slave circuits are organized in a vertical column fashion so that data may be shifted vertically up or down the slave latches as provided from the master latch. Feedback circuits from the master latch to various positions within the slave latch column permit the data to be selectively transferred from one horizontal level to the prior horizontal level for placing in the vertical column.

Abstract: A memory circuit has a plurality of data storage locations and an address associated with each data storage location. A first decoded address storage circuit stores a first decoded memory address and outputs the stored first decoded memory address. A second decoded address storage circuit stores a second decoded memory address and outputs the stored second decoded memory address. An address access circuit is coupled to the output of the first decoded address storage circuit and accesses the data storage location associated with the first decoded memory address in response to the first decoded memory address being output from the first decoded address storage circuit. A control circuit is coupled to the first decoded address storage circuit for controlling the transfer of decoded memory address information from the second decoded address storage circuit to the first decoded address storage circuit.

Abstract: A direct current sum bandgap voltage comparator for detecting voltage changes in a power supply. The direct current sum bandgap voltage comparator includes a summing node, current sources connected to the summing node and the power supply, and an indicator circuit connected to the summing node. Each current source supplies a current to the summing node wherein the summing node voltage level is responsive to the currents supplied. The indicator circuit is responsive to changes in the summing node voltage level and generates at an output a logical signal at one state when the summing node voltage level is greater than a predetermined value and generates the logical signal at the output at another state when the summing node voltage level is less than the predetermined value, the predetermined value corresponding to a preselected power supply voltage.

Abstract: An improved semiconductor package is provided wherein the mounting pad for the semiconductor is made from a material selected from the group consisting of aluminum nitride, diamond, alumina, and boron nitride.