Abstract: A circuit and method configured to generate a variable impedance. The circuit may comprise a voltage controlled resistor configured to generate the variable impedance in response to (i) a first transistor configured to receive a first control signal and (ii) a bias transistor configured to receive a bias signal. In one example, the variable impedance may be generated in further response to a clamp transistor.

Abstract: A current source varies the bias current to a differential amplifier according to fluctuations in the supply voltage. In this manner, the operating point of the differential amplifier is automatically adjusted to compensate for variations in the supply voltage. Adjusting bias current in this manner provides for a reduction in power dissipation. The current supply is coupled to the differential amplifier in such a manner that a current mirror is not required to be connected between the differential amplifier and the inverter. Eliminating the need for such a current mirror is advantageous in reducing the number of gate delays and thereby increasing the speed of a level translator to which the current source is coupled.

Abstract: A high speed level translator is disclosed in which an ECL differential input signal is applied to a differential input amplifier, amplified, and converted to a single ended intermediate signal. An inverter circuit receives the intermediate signal and outputs a signal indicative of the polarity of the ECL differential input signal. The differential amplifier is biased with a current source which varies the bias current according to fluctuations in the supply voltage such that the operating point of the differential amplifier is automatically adjusted to compensate for variations in the supply voltage. Adjusting the bias current in such a manner allows for a reduction in power dissipation over conventional level translators. Further, since the differential amplifier is configured to provide a single ended intermediate signal, a current mirror is not required to be connected between the differential amplifier and the inverter.

Abstract: A method for fabricating a BiCMOS device to achieve a maximum performance through a minimum processing steps, in which the BiCMOS device comprises high integration and high performance MOS transistors, self-aligned metal contact emitter type bipolar transistors having high load driving force, high performance matching characteristics and high integration, and self-aligned polycrystalline silicon emitter type bipolar transistors having high integration and high speed characteristics in low current, thereby being used in high integration, high speed digital and precise analog system. Said method comprises a plurality of fabrication steps including ion-implantation, formation of thin film oxide layer, deposition of nitride layer, etching of oxide layer, formation of windows and others, alternately or/and sequentially in a single chip substrate.

Abstract: A method with less processing steps for making a BiCMOS semiconductor device which can be used both in high-integration, high-speed digital devices and in precise analog devices by forming within a single substrate a CMOS transistor, a metal contact emitter bipolymer transistor having the high load driving power and highly effective matching characteristics, and a polycrystalline silicon emitter bipolar transistor having a high-speed characteristic at a low current level. Said device includes a first and a second MOSFET, and a first and a second bipolar transistor on a first conductivity-type silicon substrate, wherein performing a second conductivity-type of ion-implantation for producing a first substrate region to thereon form the first MOSFET, and a third and a fourth substrate region to thereon form the first and second bipolar transistors, respectively on said substrate. The second MOSFET is subsequently formed in a second substrate region being located between the first and third substrate regions.

Abstract: This invention provides a method for fabricating a semiconductor device comprising the steps of forming buried layers on the silicon substrate; etching an epitaxial layer after said layer is grown up, the step further including the processes of etching selectively the silicon epitaxial layer of well region on which a high speed bipolar transistor is formed to be thin and keeping the silicon epitaxial layer of well region on which nMOS transistor is formed remained the same thickness as grown up; and forming a pMOS transistor, a nMOS transistor and a bipolar transistor. High efficiency and high integration is easily attained in fabricating the high speed bipolar transistor and high performance CMOS transistor on same chip and by reducing the difficulty in processing according to the method of present invention.

Abstract: A BiCMOS inverter circuit having complementary MOS transistors and complementary bipolar transistors enables a high speed inverting operation as well as high degree of integration when it is fabricated on a semiconductor chip. The inverter circuit may further include another complementary MOS transistors to allow the logic output to be advantageously full switched in the range of V.sub.cc -0 V keeping the high speed operation.

Abstract: A method for fabricating a BiCMOS device to achieve a maximum performance through a of minimum processing steps, in which the BiCMOS device is exemplary for its high integration and high performance MOS transistors, self-aligned metal contact emitter type bipolar transistors having high load driving force, high performance matching characteristics and high integration, and self-aligned polycrystalline silicon emitter type bipolar transistors having high integration and high speed characteristics in low current, thereby being used in high integration, high speed digital and precise analog system. The method includes a plurality of fabrication steps including ion-implantation, formation of a thin film oxide layer, deposition of a nitride layer, etching of the oxide layer, formation of windows and others, alternately and/or sequentially in a single chip substrate.

Abstract: A digital automatic gain control system for maintaining a constant output level through attenuating or amplifying an input signal is disclosed.

Abstract: A FM detection system using a phase locked loop (PPL 20) and including: a wave shaping comparator (7) for accepting a signal V.sub.CO2 from a voltage controlled oscillator (4) which is 90.degree. out of phase with a control signal V.sub.CO1 from the voltage controlled oscillator (4), the comparator reshaping the signal to a square wave; an in-lock detector (8) for accepting the square wave and a frequency modulated input signal (VFM) to provide a sum frequency and a difference frequency; a low-pass filter (9) cutting off the sum frequency component, and filtering out the difference frequency signal when the PLL (20) is unlocked; a comparator (10) for comparing the output of the low-pass filter (9) with a reference voltage (V.sub.

Abstract: This invention is related to an integrated driving circuit which can control high voltage and power, and more particularly to a high voltage and power driving circuit by employing BiCMOS technology. The principal object of this invention is to provide an integrated high voltage and high power driving circuit which is reliable by using BiCMOS technology without external discrete components.

Abstract: This invention provides a method for fabricating a BiCMOS device, in which said device has a Si substrate of a first conductivity in which there is formed a first substrate region of a second conductivity for a bipolar transistor, a second substrate region of said second conductivity for a first MOSFET, having a source and drain of the first conductivity, and in which a part of said Si substrate is formed to provide a second MOSFET which has a source and drain of the second conductivity. A first nitride layer is used to prevent the substrate under a masking layer from oxidizing during the following oxidation processes, wherein the masking layer is composed of a oxide layer and the nitride layer. After some processes, the masking layer is removed. Implanting As impurities, a new oxide layer and a new nitride layer are deposited, wherein the role of the nitride layer is to protect a shallow emitter region.