摘要:
A compact via transmission line for a printed circuit board having preferred characteristic impedance and capable of miniaturizing the printed circuit board including a multilayer printed circuit board, and extending the frequency range of a via transmission line mounted on the printed circuit board, and a design method of the same. The transmission line has a central conductor forming an inner conductor layer boundary make up a signal via hole, a plurality of via holes arranged around the central conductor form an outer conductor layer boundary, and a plurality of conductor plates formed of a printed circuit board conductor layer, is further provided with a constitutive parameter adjustment clearance hole between the inner and outer conductor layer boundaries of the compact via transmission line, and electrically isolates to prevent cross-talk of a signal propagating through a signal via hole with other signals in a high-frequency signal band.
摘要:
A via transmission line for a multilayer printed circuit board (PCB) in which a wave guiding channel is formed by a signal via or a number of signal vias, an assembly of ground vias surrounding the signal via or corresponding number of coupled signal vias, a set of ground plates from conductor layers of the multilayer PCB, and a clearance hole. In this via transmission line, the signal via, or the number of signal vias forms an inner conductive boundary, ground vias and ground plates from conductor layers of the multilayer PCB form an outer conductive boundary, and the clearance hole provides both isolation of the inner conductive boundary from the outer conductive boundary and high-performance broadband operation of the via transmission line by means of the predetermined clearance hole cross-sectional shape and dimensions where the cross-sectional shape of the clearance hole is defined by the arrangement of ground vias in the outer conductive boundary and dimensions of the clearance hole are determined according to a method to minimize frequency-dependent return losses caused by specific corrugations of the outer conductive boundary formed by ground plates in the wave guiding channel of the via transmission line.
摘要:
The distance between an anode and a cathode of a thyristor and the anode and the cathode of a diode formed in a semiconductor protective circuit are made a small as allowable by LSI manufacturing technology, thereby achieving fast starting speed and a low internal resistance when in the conducting condition, so as to limit the rise in voltage on an internal circuit, even when a high-speed pulse is applied.
摘要:
In a semiconductor device including a semiconductor substrate, first and second external terminals, a first impurity diffusion region connected to the first external terminal, and second and third impurity diffusion regions forming a MIS transistor, one of the second and third impurity diffusion regions facing the first impurity region is connected to the second external terminal. The distance between the first diffusion region and the MIS transistor is substantially smaller than a certain value compared to conventional devices.
摘要:
Voltage clamping elements are respectively paired with first diodes, and the pairs of voltage clamping elements/first diodes are connected between a first common discharge line and power terminals selectively supplied with positive power voltage and ground voltage; however, the pairs of voltage clamping elements/first diodes can not prevent an internal circuit from excess voltage if a positive electrostatic pulse with respect to the positive power voltage is applied to the ground terminal; second diodes are connected between a second common discharge line and the terminals in such a manner as to discharge the positive electrostatic pulse through the associated forward-biased second diodes, and the internal circuit is perfectly prevented from the excess voltage.
摘要:
An input terminal and an input protective resistor of an N-type diffusion layer connected thereto are provided on a P-type semiconductor substrate. First and second N-type MOS transistors for internal circuit are connected to a grounding wiring at respective source diffusion layers. The first MOS transistor is located at closer distance from the input protective resister than the second MOS transistor. The source diffusion layer of the first MOS transistor and the grounding wiring are connected via a high melting point metal layer wiring, such as a tungsten silicide or so forth to increase a resistance to improve electrostatic breakdown potential. Accordingly, the distance between the input protective resistor and the first MOS transistor can be made smaller to eliminate dead space around the input protective resistor to enable reduction of a chip area.
摘要:
A semiconductor device includes a metallic main line connected between an external terminal and an internal circuit, and a plurality of divided protection bipolar transistors connected in parallel to one another. Each of the divided protection bipolar transistors includes a collector and an emitter composed of first and second N diffused regions formed in a semiconductor substrate which are separated from each other. Each of the divided protection bipolar transistors also includes a base formed of a portion of a semiconductor substrate between the collector and the emitter. The collector is connected to a metallic sub line branched from the main line, and the emitter is connected to ground. The plurality of divided protection bipolar transistors have an equal breakdown voltage between the collector of the divided protection bipolar transistor and the semiconductor substrate. Thus, the protection device composed of a plurality of divided protection bipolar transistors connected in parallel to one another can effectively protect the internal circuit from a short electrostatic pulse.
摘要:
A semiconductor device has an internal circuit, an output transistor and a protective transistor for protecting the output transistor and the internal circuit against an ESD-induced destruction caused by a surge pulse entering from an input/output terminal. The sum of a first distance between a contact for connecting an input/output terminal with the collector of the protective transistor and a field oxide film and a second distance between a contact for connecting the input/output terminal with the emitter of the protective transistor and the field oxide film overlying the base of the laterally formed protective transistor is made smaller than the sum of a third distance between a contact for connecting the input/output terminal with the drain of the output transistor and the gate electrode of the output transistor and a fourth distance between a contact for connecting a potential line with the source of the output transistor and the gate electrode of the output transistor. Besides, the effective channel length of the output transistor is made longer than the effective base width of the protective transistor.