SU1347168A1 - Time interval-to-volatge converter - Google Patents

Abstract

The invention relates to a pulse technique and can be used as a converter for the period of pulses to the amplitude of a sawtooth voltage. The purpose of the invention is the expansion of the conversion range. The achievement of the goal is due to the use of an additional transistor 3 connected to complementary transistors 1.2 according to the thyristor equivalent circuit, an additional transistor 3 connected by a collector g emitter in series across a constant current transistor with collector p -p- -p transistor thyristor equivalent. The base of the additional transistor 3 is connected to the connection point of the diode 9 of the capacitor 8 of the charging circuit. 2 Il. iS 0Н с b (Л с 00 N

Description

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The invention relates to a pulse technique and can be used as a tunable sawtooth generator with an amplitude proportional to the interval between pulses, which performs the function of converting time intervals to voltage.

The purpose of the invention is to expand the conversion range.

Figure 1 shows the principle electrical circuit of the proposed converter; Fig. 2 shows input and output voltage diagrams.

The converter contains a regenerative discharge cascade of transistors 1–3 and resistors 4–7, which are made according to the equivalent of a thyristor, in which the base of the transistor 3 connected by a gap emitter collector to the communication circuit between the base of a pnp n transistor 1, is connected to the capacitor 8 connected through a diode 9 to the source 10 current. The base of the transistor 1 through the diode 11 is connected to the bus 12 of the input signal

la, and the emitter of transistor 2 is connected to the supply voltage bus 13.

The Converter operates as follows.

In the pauses between the input pulses, all transistors 1–3 of the discharge stage are closed, and the capacitor 8 is charged through diode 9 from the current source 10. When the input pulse arrives, the transistor 1 is unlocked, and then the regenerative turn on of all the transistors of the discharge stage. In this case, the open and saturated transistor 1 diverts the current of the source 10. The diode 9 turns out to be reverse-biased and disconnects the input circuit of the discharge stage and the capacitor 8 from the current source 10. The capacitor 8 is discharged through the resistance of the base-emitter junction of transistor 3 and the collector-emitter gap of transistor 1. - ra 1 of saturation voltage on its collector increases and back biases trans-emitter junction

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of the resistor 3, a decrease in the collector current of the latter leads, due to the action of positive feedback, to a decrease in the current through the transistor 1 and t, e. After the transistors 1–3 of the discharge stage are locked, the process of charging the capacitor 8 begins again until the next input pulse arrives on the bus 12 of the device. According to the algorithm of operation, the converter performs the formation of a linearly increasing sawtooth voltage, the amplitude of which is proportional to the time interval between the input pulses, t, e, converting the time intervals to voltage,

In the proposed converter, the magnitude of the charging current from the source 10 is not limited from above by the switching-off current of the discharge stage, since at the discharge stage its input circuit and capacitor are disconnected from the current source 10 by reverse-biased diode 9.

The expansion of the lower conversion range is due to a decrease in the residual voltage on the capacitor, which corresponds to a decrease in the residual voltage of the discharge stage due to a decrease in the discharge current of the discharge stage by a factor of 3 compared to the usual thyristor equivalent circuit by using an additional transistor .

Claims (1)

Invention Formula time-to-voltage converter containing a capacitor and a discharge stage connected to the current source, performed on two complementary transistors covered by positive feedback according to the thyristor equivalent circuit, the first of which is connected to the common bus by the emitter and the second power supply source, characterized in that, in order to expand the conversion range, a diode and an additional transistor of the same conductivity type as the first transistor are inserted, the diode Keys in a straight polarity current between the source and the capacitor, and dopolnitel313471684 A transistor connected in series with a thyristor equivalent transistor, in a direct current mode between the terminal, is connected by a base to the junction point of the first diode and the base of the second diode and a capacitor. AT Editor I. Shulla Compiled by E. Sapezhko Tehred I. Popovich Order 5127/51 Circulation 899 Subscription VNRMPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5 Production and printing company, Uzhgorod, st. Design, 4. Corrector A, T sc