SU936423A1

SU936423A1 - Voltage-to-frequency converter

Info

Publication number: SU936423A1
Application number: SU802978982A
Authority: SU
Inventors: Павел Сергеевич Гнедкин; Елена Георгиевна Кущ; Айдар Михайлович Митлин; Евгений Вадимович Шумаров
Original assignee: Предприятие П/Я А-3697
Priority date: 1980-08-25
Filing date: 1980-08-25
Publication date: 1982-06-15

Description

(54) ПРЕОБРАЗОВАТЕЛЬ НАПРЯЖЕНИЯ В ЧАСТОТУ(54) VOLTAGE CONVERTER IN FREQUENCY

Изобретение относитс к и;змерительной технике и может быть использовано дл преобразовани напр жени в частоту электрических импульсов при пострел ении точных измерительных преобразователей , цифровых вольтметров, информационно-измерительных систем.The invention relates to a measuring technique and can be used to convert voltage into a frequency of electrical pulses when shooting accurate measuring transducers, digital voltmeters, and information measuring systems.

Известен преобразователь напр жени в частоту, выполненный по принципу периодического интегрировани с импупьоной обратной св зью, в цепи обратной св зи которого включен одновнбратор. 1.A voltage-to-frequency converter is known, made on the principle of periodic integration with an implicit feedback, in the feedback circuit of which a single-oscillator is connected. one.

Недостатком его вл етс зависимость точности от стабильности длительности импульса одновибратора.Its disadvantage is the dependence of accuracy on the stability of the pulse duration of the one-shot.

Известен преобразователь напр жени в частоту, содержащий интегратор, выход которого подключен к входу компаратора, конденсатор, перва обкладка которого подключена к общей шине, а втора через первый ключ к входу интегратора и через второй ключ - к источнику эта- noiffloro напр жени , первый оДновибра- тор, вход которого подключен к выходуA voltage to frequency converter is known, which contains an integrator, the output of which is connected to the input of a comparator, a capacitor, the first lining of which is connected to the common bus, and the second through the first key to the input of the integrator and the second switch to the source of the noiffloro voltage - torus, the input of which is connected to the output

компаратора, а выход - к управл ющему входу ключа 2 .the comparator, and the output - to the control input of the key 2.

НёДЬстатком его вл етс наличие погрешности, обусловленной задержкой запирани одного из ключей, в результате чего оказываетс возможным однс временное протекание тока через оба ключа.Its failure is the presence of an error due to the delay of locking one of the keys, as a result of which one-time current flows through both keys.

Цель изобретени - повышение точности преобразовани .The purpose of the invention is to improve the accuracy of the conversion.

10ten

Поставленна цель достигаетс тем, что в преобразователь напр жени в частоту, содержащий интегратор, .выход которого подключен к входу компаратора, конденсатор, перва обкладка которого The goal is achieved by the fact that in a voltage to frequency converter containing an integrator, the output of which is connected to the input of a comparator, a capacitor, the first plate of which

15 подключена к бщей шине, а втора через первьШ ключ к входу интегратора и через второй ключ - к источнику эталонного напр жени , первый одновибратор , вход которого подключен к выходу 15 is connected to the common bus, and the second through the first key to the integrator input and through the second key to the source of the reference voltage, the first one-oscillator, the input of which is connected to the output

Claims

20 of the comparator, and the output to the control input of the second key, a second one-shot and a delay element are introduced, and the output of the second one-shot is connected to the second key and connected to the output of the second one-shot. On f | yy, 1 shows the functional diagram of the proposed converter; FIG. 2 shows timing diagrams explaining his work. The converter (Fig. 1) contains integrator 1, capacitor 2, the first lining of which is connected to the common bus, and the second through the first switch 3 to the input of the integrator 1, and through the second switch 4 to the source 5 of the reference voltage. The control input of the key 3 is connected to the output of the one-shot 6. The output of the Integrator 1 is connected to the input of the comparator 7, the output of which is connected to the input of the one-shot 8. The output of the one-shot 8 is connected to the control input of the key 4 and through the delay element 9 to the control input one-shot 6. In FIG. 2 is designated: ,, - the output voltage of the integrator 1; the trigger voltage of the comparator 7; the voltage at the output of the comparator 7; OQQ is the voltage at the output of the single-shot 8; Ugan is the voltage at the output of the one-shot 6. The device operates in a specific manner. Under the influence of the input signal, the output voltage of the integrator varies linearly. When the voltage reaches the threshold of the comparator 7, a pulse from the output of the latter (Fig. 2) starts the one-shot 8, a pulse of duration t at the output of the one-shot 8 opens the key 4, which is in a closed state, and through the delay element 9 starts the one-shot 6, Impulse with the release of the last lasting Su | closes. key 3; In this case, the comparator 2, charged to the reference voltage of source 5, is discharged at the output of integrator 1, as a result of which the integrator returns to the initial level. At the end of the pulse of the one-shot 6, the switch -3 opens, and after the end of the pulse of the one-shot 8, the switch 4 closes, ensuring the charge of the comparator from the source. Then the whole cycle is repeated. As can be seen from the timing diagrams (Fig. 2), if you select the duration. ® -delay time of delay element 9, Trj is the delay time of locking key 3, and time tj is longer than the delay time of locking key 4, the simultaneous presence of keys 3 and 4 in the open CONDITION is eliminated, resulting in improved conversion accuracy. Claims of the Inverter Voltage to frequency converter containing an integrator, the output of which is connected to the comparator input, a capacitor, the first lining of which is connected to the common bus, and the second through the first key to the integrator input and through the second switch to the reference voltage source The first single input, whose input is connected to the comparator output, and the output to the control input of the second key, characterized in that, with an accuracy circuit, BTopdt one-shot is entered into the delay element, and the output is second one-way The mouth is connected to the control input of the first key, and the output of the first one-shot through the delay element is connected to the input of the second one. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 651478, cl. H 03 K 13/20, 01,12,77. 2, USSR Author's Certificate No. 492036, cl. N OZ K 13/20, 17,04.73 (prototype ;.