Abstract: What is described is a high efficiency voltage doubler (100). The high efficiency voltage doubler (100), has a charge-pump capacitor (30), an inverter (18), a coupling capacitor (24), a complementary switch pair (16), a DC biasing circuit (102), a charging circuit (106), and an input circuit (108). This structure is adapted for use in an integrated circuit, and provides the advantage of maximizing voltage doubled power output and minimizing current consumption with a minimal number of components.

Abstract: A temperature compensated crystal oscillator (10), has a crystal oscillator circuit (12), a voltage controlled reactance element (30), a temperature compensation network (50), and a programmable DC-DC converter network (60) having an output (62) connected to the voltage controlled reactance element (30), or the temperature compensation network (50) or both. The DC-DC converter network (60) provides the capability of operating over an extended voltage range, by increasing the supply voltage to a level necessary to operate the voltage controlled reactance element (30). Much of this structure is adapted for use in an integrated circuit, and provides the advantages of minimizing power and current consumption.

Abstract: A low current oscillator/buffer amplifier configuration is disclosed which provides a simple, inexpensive, low power oscillator with reduced harmonic output. Buffer 60 is coupled to the resonant tank circuit 58 of oscillator 50 by means of impedance transform network 70. This technique of tapping directly from the tank provides a buffered output signal having low harmonic content. Furthermore, impedance transform network 70 permits coupling feedback amplifier 52 to buffer amplifier 62 in a totem-pole amplifier stage configuration. This feature provides a significant current savings over conventional oscillator/buffer circuits. The instant invention is particularly well adapted for use as reference frequency oscillators in portable radio applications.

Abstract: An integratable circuit is utilized for generating a temperature varying control voltage to be applied to a varactor diode to temperature compensate a crystal oscillator. The temperature compensating circuit has a middle range circuit for creating a substantially linear current versus temperature variation in a middle temperature range, a cold-temperature range circuit operative below a predetermined temperature for creating a non-linear current versus temperature variation a hot-temperature range circuit operative above a predetermined temperature for creating a non-linear current versus temperature variation and circuitry for summing said currents and generating a voltage proportional to the current sum. The control circuit, which requires a regulated supply voltage, uses a diode string and differential amplifiers to generate the desired current versus temperature variation.

Abstract: A Colpitts type oscillator having a tank circuit including a crystal, a voltage variable capacitor and split capacitors with a first inductance including a coil connected in series with the crystal and a second inductance including a coil connected in parallel with the series connected coil and crystal and a second coil connected in series with one of the capacitors and the series combination connected in parallel with the first coil of the second inductance, said first and second inductances operating to neutralize the C.sub.o of the crystal, providing an impedance transformation between the crystal and the tank circuit, and improving the stability of the oscillator over a substantially increased warp range.