Abstract: The invention relates to an amplifier arrangement with load independent saturation detection, including an input stage (7) having a first and a second input terminal (5, 6), an output stage (8) coupled to the input stage (7) and having at least one output transistor (T1, T2), and an output terminal (4) connected to the first input terminal (5) via a coupling network (R1, R2, C). In order to obtain a detection signal when the at least one output transistor (T1, T2) becomes saturated, there is provided a detection device, (16) coupled to the input stage (7) to detect, during operation, an amplitude difference between a signal (V.sub.i) to be amplified, which signal is applied to the second input terminal (6), and a portion (V.sub.t) of the signal (V.sub.o) appearing on the output terminal (4), which portion is applied to the first input terminal (5) via the coupling network (R1, R2, C).

Abstract: A fully integratable bridge amplifier comprises two identical amplifiers (1; 5) each being provided with a first input stage (20; 40) whose inputs constitute the first non-inverting inputs (2; 6) and the first inverting inputs (3; 7) of the amplifier, a second input stage (29; 50) whose inputs constitute the second non-inverting inputs (28; 49) and the second inverting inputs (27; 48) of the amplifier, and an output stage (25; 45). The first inverting input (3; 7) of each amplifier (1; 5) is connected to the output (12) of a buffer amplifier (9) via a first resistor (R.sub.6 ; R.sub.9) which together with a second resistor (R.sub.5 ; R.sub.8) constitutes a negative feedback network between the output (4; 8) of the amplifier (1; 5) and the first inverting input (3; 7). The first non-inverting input (2; 6) is also connected to the output (12) of the buffer amplifier (9). This output (12) and consequently the first inputs (2, 3; 6, 7) of the amplifiers (1; 5) are at half the supply voltage with respect to the d.

Abstract: In an output amplifier (20) which is operated in class AB with the aid of quiescent-current means (40, 50) and which comprises first output-transistor configuration (T.sub.10 -T.sub.14) and a second output-transistor configuration (T.sub.15 -T.sub.17) with output transistors (T.sub.14, T.sub.17) of the same conductivity type, the drive signals for these output-transistor configurations are derived from the output signal (V.sub.i) of the input amplifier (10) by means of a single voltage-to-current converter (30). In the case of a positive drive of the first output transistor configuration (T.sub.10 -T.sub.14) this converter (30), together with the first output-transistor configuration (T.sub.10 -T.sub.14) and a load (R.sub.L) connected to the output (5) of the output amplifier (20), constitutes an amplifier configuration with full negative feedback, while in the case of a positive drive of the second output transistor configuration (T.sub.15 -T.sub.

Abstract: Short-circuit protection of the load of an output amplifier by means of a non-linear coupling between the output and a d.c. bias point of the amplifier.