Abstract:
A computer system is provided that loads a computer program, in a reverse order, into a memory device having one or more defective memory cells. The program is organized into code modules with each code module including at least one complete instruction, or data block. The last code module of the program is loaded first into the last or highest addresses of the address space allocated in the memory for the program. Thereafter, the code module preceding the last loaded code module of the program is loaded into the addresses preceding the previously-loaded addresses. The subsequent code modules are loaded into successively lower memory addresses in a reverse fashion until the first code module of the program is loaded into memory. As each code module, or the codes that make up the code module, are loaded, each loaded memory address is checked for a defective cell. A JUMP instruction is created and inserted into the original program code preceding the defective memory address to bypass any defective memory cell without interrupting the intended operation of the instruction steps that are loaded into the memory. In addition, a JUMP instruction is inserted into the memory start address so that a processor is forced to begin execution at the memory address containing the first byte of the first code module. Certain byte codes that include referenced addresses are then modified to correct any address-referencing that may be changed due to the insertion of the JUMP instructions, and then loaded into the appropriate addresses in the memory.
Abstract:
A transient negative voltage pump circuit pumps the ESD voltage to a negative voltage. The negative voltage with the ESD voltage are used for early triggering of an SCR structure on the integrated circuit. In one version of the present invention, a pn junction diode of the SCR device is used as part of the negative voltage pump circuit. This saves the layout area while improving the ESD performance. The present invention improves the ESD performance of an SCR ESD protection circuit which is used for protecting the power bus or an IC pin during an ESD event.
Abstract:
For low-voltage and high-speed operation of a MOSFET in an integrated circuit, a small voltage is applied to a source node, causing slight forward bias of the source junction and thereby reducing its threshold voltage. Due to the combined effects of the bias at the source node and a body effect, the reduction in threshold voltage is larger than the absolute value of the source voltage being applied. A performance improvement over simply applying a bias voltage to the body (well) results. Detection of an event can be used to apply the performance boost to a critical path in the integrated circuit only when needed. Upon detection of a logic event, which determines that a signal will propagate through the critical path shortly thereafter, the source-node bias for circuit elements in the critical path can be adjusted in time for a speed improvement. However, the source remains at another potential when no signal is passing through the critical-path, to save power when not boosting speed.
Abstract:
An ESD protective device for protection of an integrated circuit (IC) package from electrostatic discharge damage. The ESD protective device protects the internal circuit of the IC connected to wired pins of the IC package against ESD damage due to ESD stress in neighboring no-connect pins. The ESD protective device includes an ESD protective unit coupled to the power bus and a bonding pad coupled between this ESD protective device and the no-connect pin. The ESD protective unit causes ESD stress applied to the no-connect pin to be diverted to the power bus, thus preventing ESD transfer between a no-connect pin and an active pin, which could damage the internal circuit.
Abstract:
A transient voltage-pump circuit pumps the ESD voltage to a higher voltage. The pumped-high transient voltage is used for early triggering of an SCR. In one version of the present invention, a pn junction of the SCR device is used as part of the voltage-pump circuit. This saves the layout area while improving the ESD performance. The present invention improves the ESD performance of an SCR ESD protection circuit which is used for protecting the power bus or an IC pin during an ESD event.
Abstract:
A pin-assignment method is provided for use on an IC package to arrange pin connections. The pin-assignment method can allow an improvement in the electro-static discharge (ESD) protection capability for the IC chip packed in the IC package. Specifically, the pin-assignment method organizes the no-connect pins of the IC package into groups and then assigns each of the two pins that bound each no-connect pin group to be connected to a power bus of the IC chip. This allows for an increased ESD protective capability for the no-connect pins. Moreover, the pin-assignment method can simplify the wiring complexity of the IC package.
Abstract:
A dual-node capacitor coupling technique is used to lower the trigger voltage and to improve the uniform turn-on of a multi-finger MOSFET transistor. Preferably, each MOSFET is an NMOS device. Specifically, each NMOS device includes a capacitor that is connected between the gate of the NMOS device and the pad terminal. A first resistor is connected between the gate and the p-well, while a second resistor is connected between the p-well and the grounded source. For a positive ESD pulse to VSS, the p-well is pulled up to approximately 0.7 V during the initial ESD event, such that the source junction is forward biased and that the trigger voltage of the NMOS device is lowered. At the same time, the gate voltage is coupled within the range of approximately 1 to 2 V to promote the uniform turn on of the gate fingers of the NMOS devices during the initial ESD event.
Abstract:
A MOSFET structure for an ESD protection circuit in a semiconductor IC device having segmented diffusion regions. The transistor includes a gate having an extended strip-shaped structure formed on the substrate of the IC device. A well region is formed in the substrate on a first side of the gate structure. A first drain diffusion region is formed in the well region, and a second drain diffusion region is formed partially inside the well region. A source diffusion region is formed in the substrate along a second side of the gate structure, opposing the first side. A field oxide layer is formed over the surface of the substrate, the field oxide layer comprises a number of finger-shaped extensions originating from the drain side of the transistor and extending into the source side of the transistor. The finger-shaped extensions divide the second drain diffusion region into a number of parallel-aligned segmented diffusion regions.
Abstract:
A position detector for a scanning beam comprising a plurality of rows of spaced apart sensors. Each row of sensors includes a plurality of logic zero sensors and a plurality of logic one sensors which are arranged in alternating logic order. Each row is arranged such that it is symmetrical about its center. Equal areas of logic zero sensors on each side of the center are equal distances away from the center and equal areas of logic one sensors on each side of the center are equal distances away from the center to substantially cancel out any background light effects on the sensors.
Abstract:
The present invention consists of a photocell array to determine the cross-scan position of a laser beam. The array consists of multiple rows of elongated photocells oriented perpendicular to the main scan direction of the laser beam with each row of photocells representing one bit of data. Furthermore, each row consists of alternating types of photocells, one type representing a logic 1 and the other type representing a logic 0. As the laser beam crosses this array, it energizes certain photocells on each row such that its output is a binary number that identifies the position at which the laser beam crosses the array. To improve the accuracy of the binary output, the pitch between the photocells of each row should not be reduced to less than 1/4 of the width of the laser beam. If greater accuracy is needed, the photocells should be offset while keeping the pitch between the photocells constant at a pitch not less than 1/4 of the width of the laser beam.