Dong-Chual Kang

An efficient built-in self-test algorithm for neighborhood pattern sensitive faults in high-density memories

As the density of memories increases, unwanted interference between cells is increased and testing high density memories for a high degree of fault coverage can require either a relatively large number of test vectors or a significant amount of additional test circuitry. In this paper, a new thing method and an efficient BIST algorithm for NPSFs are proposed. Instead of the conventional five-cell and nine-cell physical neighborhood layouts to test memory cells, a four-cell layout is used. This four-cell layout requires smaller test vectors and shorter test time. A CMOS column decoder and the parallel comparator proposed by P. Mazumder and J.H. Patel are modified to implement test procedure which is appropriate for the four-cell layout. Consequently, these reduce the number of transistors used for a BIST circuit. Also, we present properties of the algorithm, such as its capability to detect stuck-at faults, transition faults, and conventional pattern sensitive faults.

Design of an 8-bit neuron MOSFET A/D converter using subranging method

An 8-bit subranging neuron MOSFET A/D converter circuit was designed and implemented. This neuron MOS A/D converter shows flexible operation and simple structure comparing with the common CMOS A/DC circuit. It is composed of two 4-bit A/D subconverters, 4-bit D/A subconverter, subtracter and 8-bit output latch, each subcircuit was simulated separately by using HSPICE.

A Development of the System to Prevent Unintended Sudden Acceleration by Controlling the Transmission of a Vehicle

In this paper, we proposed the method to prevent sudden acceleration occurred in a vehicle when drivers put into gear. By controlling the oil pressure of the transmission, the engine can be safely controlled and the power is not transmitted into wheels on the condition of the sudden start. The TCU (transmission control unit) can control the oil pressure with several solenoid valves to shift gears. The control of hydraulic pressure gives several advantages. It puts out gear and keeps an engine at idle when unintended sudden acceleration is occurred. If the engine is turned off on driving by the sudden start, the brake system is stopped and a driver runs into danger. The sudden start is generally occurred within a short time. If the transmission is controlled at that time, the driver and the car are safe. This paper proves that the system of preventing the sudden start is one of the safest systems and is easily applicable to a vehicle. The main algorithm of the developed system is small enough to be embedded into the ECU (electric control unit) of a vehicle.

A new test algorithm for bit-line sensitive faults in super high- density memories

As the density of memories increases, unwanted interference between cells and coupling noise between bit-lines are increased and testing high density memories for a high degree of fault coverage can require either a relatively large number of test vectors or a significant amount of additional test circuitry. Conventional test algorithms have focused on faults between neighborhood cells, not neighborhood bit-lines. A new algorithm for NPSFs, and neighborhood bit-line sensitive faults (NBLSFs) based on the NPSFs are proposed. Instead of the conventional five-cell and nine-cell physical neighborhood layouts to test memory cells, a three-cell layout which is a minimum size for NBLSF detection is used. To consider faults by maximum coupling noise by neighborhood bit-lines, we added refresh operation after write operation in the test procedure (i.e., write/spl rarr/refresh/spl rarr/read). Also, we show that the proposed algorithm can detect stuck-at faults, transition faults, conventional pattern sensitive faults, and neighborhood bit-line sensitive faults.