SU953724A1 - Voltage (current) to frequency converter - Google Patents

Description

(54) VOLTAGE CONVERTER (CURRENT) TO FREQUENCY

The invention is inclined to form a measuring instrument and can be applied to construct analogue converters. A voltage to frequency converter is known, comprising an integrator, a threshold device and a switch connected in parallel with the integrating capacitor. It has a large conversion error due to the finite discharge time of the integrating capacitor, which affects the threshold drift conversion ratio of the device. The transducer to frequency converter is known to contain an integrator, the output of which is connected to the input of the threshold device, waiting for a multivivator whose input is connected to the output the threshold device, and the output is the input to the form of pulse pulses of two volts of the terminal, the output of which is built up with Eosod of the integrator ZJ. Ovnako when trying to get it in a crib in which the driver of feedback loops does not have time to discharge the integrating capacity, the device is in overload mode. When you are driving, the frequency of the following pulses at the output may be absent or remains constant, equal to the natural frequency of the waiting Multivibrator. In this case, the absence of information on the presence of overload at the device output can lead to errors and malfunction in the system, of which the known device is a component. The purpose of the invention is to additionally dehumidify the function of signaling an overload on the input signal. The goal is achieved in that the voltage-to-frequency converter contains an integrator, the output of which is connected to the input of the threshold device, a waiting multivibrator, the input of which is connected to the output of the threshold device, and the output to the input of the pulse-forming body of a stable vapsecond terminal, which is connected from the entrance

the integrator’s house, the first trigger, the information input of which is connected to the output of the threshold device, and the synchronization input of the output of an exiting multivibrator, and the second trigger, the first installation input of which is connected to the output of the first trigger, and the second installation input are connected to the installation input of initial state. The drawing shows the functional electrical circuit of the converter.

The device contains an integrator 1, the output of which is connected to the input of the nopt device 2, a standby multivibrator 3, the input of which is connected to the output of the threshold device 3, a pulse shaper of a stable volt-second area 4, the input of which is connected to the output of the standby multivibrator 3, and the output of the integrator 1, trigger 5, whose information input is connected to the threshold output, device 2, and the synchronization input to the multivibrator output 3, trigger b, the setup input of which is connected to the trigger output 5, and the second mouth Set Input with input 7 of the setup to the initial state. From output 8, an overload signal is removed, from output 9, the output frequency.

The device works as follows.

In normal operation, when the output voltage of the integrator 1 reaches the voltage level of the threshold device 2, the latter switches to the logical 1 state at the output and starts the waiting multivibrator 3, which produces a pulse of a certain duration and, in turn, resolves the driver 4 to generate a pulse This pulse discharges the integration capacitor. By the time the discharge pulse is approached, the voltage at the output of integrator 1 will be less than the response level of threshold device 2, and it will switch to the logical O state. Therefore, the falling edge of the waiting driver will trigger a logical D from the output of the threshold device 2 The trigger state 6 is not iam & nits.

When acting on the input transducer of the corresponding state

then, the output of the integrator 1 does not have time to decrease by the moment the discharge pulse terminates below the threshold threshold threshold, which remains in a logical state, and this condition is trailing the back edge of the waiting multivibrator to trigger 5, and the awaiting multivibrator switches to generator mode, having forced the shaper 4 to periodically unload the integrator 1. Logical 1 from the output of flip-flop 5, flip-flop 6 will be set to the logical 1 state. Flip-flop 5 will be maintained for the whole time overload press. After the end of the action of the overload voltage, the trigger 5 returns to the logical O state. The trigger state 6 returns to the initial state with the arrival of the initial setup pulse to the input 7.

Thus, due to the distinctive features of the invention, an additional function of signaling overload on the input signal is carried out.

Claims (2)

1.Pr tpynikov V.A. Integrating ashfrO№1e voltmeters of direct current. L., Energie, 1976, p. 132-135. 2. Electronics (Russian translation). 1972, No. 19, p. 54-59 (prototype). Hh-a,