Abstract: A differential amplifier with adjustable offset includes a differential pair, a controller, an offset adjuster and an output stage. The differential pair and the output stage can be standard implementations such as, for example, a source-coupled PFETs and a folded-cascode output stage. The offset adjuster includes transistors that can be selectively enabled to form a composite transistor that is connected in parallel with at least one transistor of the differential pair to, in effect, increase the size of the transistor of the differential pair. The controller can reduce offset by causing the offset adjuster to increase the effective size of the appropriate transistor of the differential pair to compensate for device mismatch in the differential amplifier.

Abstract: A precision voltage reference circuit for generating a constant reference voltage over a range of operating temperatures uses a bandgap voltage generator which is compensated with replicated currents fed back from the bandgap stage as control currents. These currents are attenuated and fed back in proper proportions to correct for bias conditions which would otherwise vary with temperature.

Abstract: An autocalibrated voltage reference includes a continuous time reference and a switched calibration reference where continuous time reference is dynamically adjusted to match the switched reference such that the temperature drift and long term drift of the continuous time reference is matched to the low temperature drift of the switched reference and further resulting in improvement of the long term drift of the switched reference and of the entire system.

Abstract: An electronic gain control circuit and method are disclosed for providing gain control. The gain control circuit is adaptable for use with differential amplifiers to control the gain thereof and is suitable to be fabricated in monolithic integrated circuit form. The gain control circuit utilizes voltages generated by currents established through diodes to obtain a differential gain voltage to linearly vary the gain of the amplifier. In a preferred form, the amplifier consists of first and second differentially connected transistor pairs with each pair commonly connected to a respective collector of an input differential stage. A constant current source supplies a constant current through a first diode string and is coupled to a common node between the transistor pairs for providing a fixed voltage thereat.