Abstract: A complementary flipflop circuit is provided combining high speed with substantially zero DC current flow in standby mode between clock signal transitions. A differential input stage having n-channel transistors is gated by one phase of a clock signal for storing a complementary data input signal at the drains of p-channel load transistors which are cross-coupled to the first and second outputs of the differential input stage. The zero DC current flow is provided as the complementary configuration of the p-channel load transistors and the n-channel transistors of the differential input stage maintains isolation between the power supply conductors between transitions of the clock signal thereby reducing the average power consumption. The high operation bandwidth is achieved by using only a single p-channel transistor between the power supply conductors with gallium arsenide material.

Abstract: An input buffer includes an input circuit (80), a pair of complimentary outputs (52,54) and a differential ampliifer (12). The input buffer includes a pull-down diode (90) arranged in parallel with pull-up diodes (84, 86, and 88), coupled between the buffer input (82) and the differential amplifier input (32). Pull-up is achieved through the low impedance path of the pull-up diodes, eliminating a need for a high value resistor. Pull-down is achieved through the pull-down diode in series with a resistor (92). This arrangement provides high speed of operation, while reducing current consumption.

Abstract: A divider circuit for producing a quotient result within one cycle time is provided. The invention utilizes combinational circuitry for performing a division operation by computing a scaled reciprocal of the denominator, and multiplying the scaled output by a similarly scaled numerator. The denominator is scaled such that it falls within a predetermined range, and the reciprocal value may be looked up from a memory device such as a ROM. The output of the multiplier may also be scaled in order to produce the desired result. The resulting quotient has a controlled error over a wide range of numerator and denominator input values.

Abstract: A crystal oscillator circuit for use with overtone crystals restricts its resonant frequency to either fundamental or overtone frequencies. An inverting amplifier, which provides 180 degrees of phase shift by inverting an input signal, includes components which effectively provide another 180 degree phase shift at a particular frequency by adding a time delay. The 180 degree phase shift by a signal inverting amplifier, with the included 180 degree phase shift provided by the time delay comprises an oscillator by the addition of a crystal with a resonant frequency equal to the particular frequency determined by the time delay. Suppression of unwanted oscillation frequencies is accomplished by adjusting a current source, which changes time delay, without using inductors or other reactive components.

Abstract: Diode load emitter coupled logic circuits is described that utilizes forward biased diodes in the load circuits. The load circuits may be comprised of a single diode or two or more diodes connected in series. If a single diode is used in the load circuits, the slope factor of the diode must be greater than or equal to the slope factor of switching transistors in the logic circuit. External bias circuitry provides a bias current which can be varied for varying the frequency of operation of the logic circuit. High speeds at low power dissipations can be obtained since the switching transistors in the logic circuits do not switch completely on and off.

Abstract: A high frequency divider suitable for use in a frequency synthesizer using a dual modulus prescaler and two counters to achieve high speed and low current drain. The input signal is alternately divided by one of the two moduli in the prescaler and then alternately divided by one of the two counters. Each of the two counters is reset while the other is counting thereby reducing circuit complexity and increasing circuit speed.

Abstract: An improved frequency synthesizer suitable for use in mobile and portable radio applications using multiple dual modulus prescalers to achieve high frequency operation and low current drain. A first high speed prescaler of limited size is used in conjunction with a second prescaler to avoid the use of one large high speed prescaler to attain high frequency operation. Consequently, the frequency synthesizer can be constructed using only a minimum amount of high speed, high current drain logic thereby reducing costs and power consumption.

Abstract: Symmetrical integrated transistors and drive circuitry provide low loss bilateral analog crosspoints for a switching matrix. Each crosspoint comprises a high performance PNP lateral transmission switching transistor and an associated NPN vertical drive transistor formed over a common n-type buried tub in a p-type substrate. Individual crosspoints, including the transmission transistor and the drive circuitry, are isolated by means of frame shaped p-type isolation regions lying outside the buried tub. The collector of the NPN drive transistor and the base of the PNP transmission transistor are ohmically connected by means of the buried tub. Accordingly, although the transmission transistor and the drive transistor are merged in a single isolation region, current drive to the PNP transistor is by means of the NPN transistor as a functionally independent device.

Abstract: Several embodiments of isolated lateral transistors are shown. The emitter and collector electrodes of each embodiment are formed in the same processing step as the region which isolates the transistor from other structures. Consequently, the emitter and collector electrodes are each relatively heavily doped and extend to an underlying buried layer over which the transistor is formed. The heavy doping and the deep penetration of the collector and emitter diffusions tend to increase transistor efficiency; and since the emitter and collector electrodes are formed in the same processing step as the isolation diffusion, there is a reduction in processing complexity.