Abstract: A driving circuit is provided for a power transistor connected to an inductive load. A detection resistor is placed between ground and the emitter of the power transistor. The driving circuit has a first portion which is capable of generating a first current which is a non-linear function of the voltage across the detection resistance. A second portion of the driving circuit is used to generate a base current for the power transistor that is proportional to the first current. The non-linear function of the first current compensates for the non-linear gain with respect to collector current of the power transistor.

Abstract: A power output stage has a Darlington-pair circuit (11, 12) for switching an inductive load, especially the ignition coil of an internalcombustion engine. In order to predetermine the operating mode of the power output stage, a switch (24) is provided which bridges the base-emitter junction of the Darlington-pair circuit (11, 12), is closed in the event of a quick disconnection of the output stage, and is opened in the event of a voltage-limited disconnection of the output stage. A voltage divider, which consists of at least two resistors (16, 18) and bridges the switching junction of the Darlington-pair circuit (11, 12), is connected by means of its pick-off to the junction point between the switch (24) and the base of the Darlington-pair circuit (11, 12), the switch (24) being connected in parallel with a part (18) of the voltage divider.

Abstract: A biasing device which is in thermal contact with an RF device for actively biasing the RF device operating in quasi-linear modes. The biasing device provides a low impedance current source with high current capability to the base of the RF device. The biasing device includes three specially-processed transistors. The second and third transistors are connected such that their base-emitter and base-collector junctions are in parallel effectively forming two exceptionally low turn on series diodes. The result of reducing the resistances of the second and third transistors, by configuration and processing, is that they turn on slightly before the RF device is biased to its quiescent point.

Abstract: The invention relates to a voltage limiter for a transistor circuit with semiconductors (T.sub.20 and T.sub.21) in the arrangement of a plurality of successive amplifier stages, with a reference element (Zener diode Z.sub.20) and with at least one voltage divider arrangement (voltage divider R.sub.21 /R.sub.22). In accordance with the invention, the reference element (Zener diode Z.sub.20) is disposed downstream of the triggering circuit of the first stage or even closer at the output of the voltage limiter circuit for reducing the oscillation tendency.

Abstract: A transistor load driving circuit characterized in that fast charge/discharge driving can be realized for a capacitive load with variation made between a large load state and a small load state, without breakdown phenomenon for the output transistors. In load driving circuit 1, there is a totem-pole-type load driving circuit 10 and a rise characteristics control circuit 20, which is connected to resistor C.sub.L by coupling capacitor C.sub.1 and acts as a constant-current functional circuit. In the case with a large load, said totem-pole-type load driving circuit 10 can perform high-speed charge/discharge operations for the load electrostatic capacitance C.sub.L. When the value is small for load electrostatic capacitance C.sub.L, the characteristic curve of totem-pole-type load driving circuit 10 becomes too steep, so that the sustain voltage of the transistor decreases, rise characteristics control circuit (20) acts to limit the collector potential of phase-splitting transistor Q.sub.