SU840953A1 - Function generator - Google Patents

Description

The invention relates to analog computing.

Known function generator comprising integrating amplifiers, OR gates and AND-NO, the pulse distributor, the pulse generator ⁵ and preob- raeovatel codes w.

A function generator is also known that contains comparison circuits that specify the position of break points, input resistors, and an output integrating amplifier that performs piecewise linear approximation of time functions [2J.

The disadvantage of these generators is! Constructive complexity.

The closest technical solution to the proposed one is generator ¹ f fictitious, containing a block of voltage dividers, an inverter, an OR element, the first input of which is the generator start input, an operational amplifier, the output of which is the generator output, an integrating capacitor included between the input and output , operational amplifier, an input current compensation element connected to the input of the operational amplifier, n master triggers, the outputs of which, in addition to the output of the η-th master trigger, are connected to the corresponding the input inputs of the voltage divider block, η threshold elements, the inputs of which are connected to the output of the operational amplifier, and the outputs with the zero state inputs of the corresponding master triggers, output., η. of the th master trigger is connected to the input of the voltage divider block through an inverter, the inverse output of each master trigger, except P'ngo, is connected to the counting input of the next master trigger by the number, the inverse output of the nt th trigger is connected to the second input of the OR element, output and which is connected to the counting input of the first master trigger, the output of the voltage divider block is connected to the input of the operational amplifier (I3

The disadvantage of this generator is its complexity, since when forming symmetric functions of time (for example, a sinusoidal type, parabolic functions, etc.), it must have separate defining triggers, threshold elements, and voltage dividers for each linear section of the ascending and descending branches. · Driven function.

The purpose of the invention is to simplify the structure of the generator when reproducing the symmetric functions of time.

This goal is achieved in that the function generator containing the voltage divider block, an inverter, an OR element, the first input of which is the generator start input, an operational amplifier, the output of which is the generator output, an integrating capacitor connected between the input and output of the operational amplifier, an input compensation element AC coupled to the input of the operational amplifier _25, η zadayu- 'boiling triggers, whose outputs are output except n-th master latch coupled to corresponding inputs blo20 ka Affairs teley voltage, threshold P ι _{3 (J} elements whose inputs are connected to the output of the operational amplifier, first and second inputs of the first master triggera- connected respectively to the output of the OR gate ₃₅ and an inverted output of the first threshold element further comprises (n-2) additional OR elements, n-2 elements NOT *, (n + 1) th threshold element, (n + 1) th trigger, switch ₄₀ and an input resistor connected between the inverter output and the input of the operational amplifier, output voltage divider unit connected to movable , Switch contact, ₄₅ a control input of which is connected to the output;

(n + 1) th master latch, the first and second stationary contacts, respectively, to the input of the operational amplifier and a 'to the input: inverter, the first and secondary ₅₀ inputs each swarm 1 -th additional OR gate connected respectively with inverted. by the output of the Ath threshold element and with direct output of the 6 +1 )th threshold element, the output of each _55th additional OR element is connected to the first and through the corresponding element NOT to the second input (i + l) -ro of the master trigger, direct

840953 4 mine The output of the first threshold element is connected to the second input of the main OR element, the first and second inputs of the nth master trigger are connected respectively to the inverse and direct outputs of the (n-1) th threshold element, the first and second inputs (n + 1 ) of the nth trigger trigger are connected to the inverse 'output of the ηth threshold element, and by the direct output of the (ϊΐ + jL) --GO' threshold element, the output of the ηth trigger trigger is connected to the corresponding input of the voltage divider block.

In FIG. I is a block diagram of a generator; in FIG. 2 is a timing diagram explaining its operation.

The function generator contains a block 1 of voltage dividers, an inverter 2, an operational amplifier 3, a capacitor 4, an input current element, an input switch 7, an element of the horn element 9 _{L of the} triggers h -2 additional 114 1 ·· 1 In-ι I П 12 ^ , ..., 12 _p _2.

The generator operates as follows, integrating compensation resistor 6, or 8, n + 1 according to

1О ₄ , ..., 10 _in , elements OR -2 elements NOT at once.

In the initial state, zero potentials appear at the direct outputs of threshold elements, ..., 9 _{n + f} , and positive potentials corresponding to a logical one appear on inverse ones. Positive potentials appear at the second inputs of the triggers 1О ₄ 10 _{п + 1} , and zero potentials appear at the first inputs, which corresponds to the zero state of the master triggers 10, ..., lC ^ _M ,

those. such when their potentials have zero potentials. The output of the operational amplifier 3 is also a zero potential (Fig. 2A). When a start pulse is applied to the input of the OR element 8, the last one with the output pulse (Fig. 26) overturns the master trigger 10 ₄ , at the output of which a rectangular step of positive voltage is formed (Fig. 2c). This voltage, reduced in the unit of voltage dividers 1 V. In accordance with the required steepness of the generated function, through the switch 7 is fed to the input of the inverter 2 and then through the input resistor 6 to the input of the operational amplifier 3. At the output of the generator there is a positive voltage increasing in time on inputs of threshold elements

9, ..., 9 _{nt <} . with adjustable thresholds. Using threshold elements 9 ₁ ..... 9 _PN , the span of the linear sections of the reproduced curve is set. ₅

When the voltage at the output of the operational amplifier 3 reaches the threshold level of the first threshold element 94 (point B, Fig. 2a) on its inverse. . ·. the output produces a negative differential pulse (Fig.2d), which returns the trigger 10 ^ to its original state and through the OR element 11 ^ and the element NOT 12 ^ overturns the trigger ΙΟ, χ (Fig.2d). At this end, <5 s, the formation of the first linear portion AB of the reproduced curve (graph of Fig. 2a) and the formation of the second portion of the BB curve begins. When the output voltage of the operational amplifier ₂₀ 3 reaches the threshold of the second threshold element 9 ^, the latter is triggered, returning a positive differential pulse on the direct output (Fig.2e) through the element OR 1 and the element NOT 12 ^ trigger 10 to its original state (Fig.2d ), and a negative edge at the inverse output through the OR element tig and the element NOT 12p overturns the trigger 10 ₅ (Fig. 2g). The ascending sections of the upper and lower boundary (Fig. 2a) form. mirrored similarly when triggered; threshold element 9 ^ (fig.2z) and trigger 10ή (fig.2i).

Upon reaching the output voltage of the operational amplifier ³⁵ Niemi response threshold nth threshold element 9η (for simplicity assume n = 4), the latter is activated (FIG. 2k) and negative differential pulse trigger tilts Ιθη + ι control switch 7. In this case, the output unit dividers voltage 1 is connected to the input of the operational amplifier 3, at the output of which a decreasing voltage is formed, the slope, which is equal to the slope of the last upstream section of the main circuit (Fig. 2a) of the reproduced curve, since it is determined by the voltage ₅ tupayu- θ conductive 10η trigger output through an appropriate divider unit L voltage when the output voltage of the operational amplifier 3 the response threshold element (point F _{ig.2a%); 55, the} latter returns to its initial state (Fig. 2h), while returning the trigger 10η (Fig. 2I) to the initial state by a negative pulse difference and overturning the same pulse through the OR elements 11η. ^ And the element NOT ¹² p-th trigger 10 _rt . ^. In this case, the formation of the second declining portion of the GW reproduced curve begins. WB and BA sections are formed in a similar way. When the output · voltage of the operational amplifier 3 reaches the threshold of the threshold element 9 _{p +} | (Fig.2l), the latter fires and overturns the trigger 10 _{η +} ι (Fig. 2m), which sets the switch 7 to the position corresponding to the connection of the output of block I to the input of inverter 2, due to which an increasing voltage begins to form at the output of the generator. Next, the generation cycle of the reproduced time function is repeated.

Using the proposed generator when playing symmetric functions allows you to reduce the number of custom elements in the generator compared with the known by half, which makes the proposed generator more simple in structure.

Claims (3)

1. USSR author's certificate No. 651376, cl. (gf15 / 20, 1979 2. US patent number 362277O, cl. 23197, published. 1971. 3. USSR author's certificate number 570O69, kl.d-On q 7/26, 1977.