HIGH-SPEED OUTPUT STAGES OF OPERATIONAL AMPLIFIERS WITH DIFFERENCING CIRCUIT CORRECTION OF TRANSITION PROCESS

Abstract

For the first time, a circuit design solution with an increased maximum output voltage rise
(decay) rate of a family of classic AB class output stages, which are the basis of many integrated
circuits of operational amplifiers (544UD1, 153UD4, A741, etc.), is presented. For this purpose,
special elements of transient process in the large signal mode are introduced into the basic circuits
of the output stages. The circuitry of this class is implemented on both bipolar (BJT) and
CMOS transistors. The results of computer simulation in the LTspice XVII simulation software
show that, in comparison with classical circuits, due to the introduction of an additional differentiating
capacitor and an input emitter repeater, the maximum rate of decay in the output voltage of
the output stages increases by more than 500 times. At the same time, the considered output stage
circuits provide output voltages with maximum amplitude from - 8.5 V to + 10 V with a relatively
low load resistance (up to 2 kOhm) and supply voltages of ± 10 V. It is shown that for small-scale
production of the proposed output stages, their execution on basic matrix crystals MH2XA031 is
recommended (OJSC “Integral”, Minsk, Belarus), which will reduce the cost-effectiveness of
manufacturing microelectronic products. The basic matrix crystal MH2XA031 based on the 3CBiT process technology allows the proposed schemes to operate at low temperatures (up to - 197 °C),
as well as under the influence of penetrating radiation with an absorbed dose of gamma quanta
(up to 1 Mrad) and a neutron flux (up to 1013 n/cm2).