JPS6112113A - Slice circuit - Google Patents

Abstract

PURPOSE:To slice surely a signal with small level to a signal amplitude by performing slicing through the use of a difference between a signal in phase to an input signal and a signal of opposite phase thereto. CONSTITUTION:When an input signal is fed to a signal input terminal 1, a signal in opposite phase to the input signal and a signal in phase to the input signal are extracted from points (b), (c) respectively. The signal at the points (b), (c) is subjected to level shift respectively by transistor (TR) Q2, Q6 and level shift diodes D1, D2 and fed to TRs Q12, Q11. Thus, the TRs Q12, Q13 use the difference between the signal (f) in phase to the input signal and the signal (d) in opposite phase thereto to apply slicing. Then in cutting a very small level to the signal amplitude, the leakage of the signal below the slice level caused by the effect of nonlinear operation is suppressed to a small value so as to slice surely the small level signal.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a slice circuit, and more particularly, to a slice circuit using transistors. The purpose is to provide a circuit that can be sliced into

Prior Art FIG. 5 shows a circuit diagram of a clip circuit previously proposed by the present applicant in the utility model registration application "Clip Circuit" dated October 27, 1981. In the same figure, the signal input to terminal 1 is taken out in reverse phase by transistors Q+ and Q2, and is supplied to transistor Q3 with a base *DCDC potential by connecting capacitor C1 and resistor R1, and is level-shifted by diode DI. is supplied to transistor Q4, while
Input No. 15 is taken out in phase with the 1-ranging metal Qs and Qs, made into a reference DC potential by the capacitor C2 and the resistor R2, and supplied to the transistor Q8.
2, the output of the transistor Q4 and the output of the transistor Q7 are respectively supplied to the transistor Qs+QIO, and a predetermined level range centered around a certain level of the input signal from the terminal 2 is cut 1-. This takes out the signal shown in Figure 6 (Δ).
As a result, it is possible to output a signal in which the pulse waveform is almost blunted even for high-frequency hexapulses.

The problem that the invention attempts to solve The above circuit consists of transistors Q3, (L+ (Q7
.

In Qa), the slice operation is performed using the difference between the reference DC potential and the human input signal, and since the potential difference in A is relatively small, especially when cutting an extremely small level with the Noburo amplitude, As shown in FIG. 6, when the low-level portion is completely cut off, there is a problem in that only the low-level portion remains as shown in FIG. 6(B).

In addition, a noise reduction circuit is provided to reduce the noise contained in the output of the above circuit, and the slice level is set approximately equal to the peak-to-peak value of the noise, as shown in FIG. The output of this noise reduction circuit has the problem of leakage of noise components, as shown in FIG. 3(B).

Means for solving the problem Iζ and its operation The present invention provides a means for solving the problem Iζ and its operation.
a constant current source connected between the base and emitter of the first and second transistors and the ground, such as a helangistor and a second helangistor that is supplied with No. 111 having a reverse phase to the input signal as a base; , a potential level shifted by a predetermined level is applied to the emitter of the first transistor with respect to the base potential of the second transistor, while applying a potential level shifted by 1 to the emitter of the second transistor with respect to the base potential of the first transistor. '(Applying a potential with a predetermined potential level shift)
level shift 1-circuit and the above first transistor.
The above problem is solved by a configuration consisting of a collector and a circuit for amplifying and extracting the difference between the signals respectively taken out from the collector of the second 1-range metal.Hereinafter, an example of the same will be explained along with the drawings. explain.

Embodiment FIG. 1 shows a circuit diagram of an embodiment of the slice circuit according to the present invention. In the same figure, the same parts as in FIG.
10 In the same figure, the differential amplifier composed of transistors Q+ and Qs is configured so that point C is balanced when there is no input signal, and point C is at the same potential by 4f. From one point C, a signal having the same phase as the input signal is extracted.

The signals at the two points C are connected to the transistor Qy.

Qa and the level shift diodes I)+ and [)2 respectively level shift the voltage and supply it to the transistor Q12゜Qu, and the transistor Qu receives the difference (Vh-q) between the potential of the point j1 and the point j1. , l~Non-jime Q 12 is turned on and off in response to the difference (Vi-e) between the potential at point i and the potential at point O, respectively, to perform a slice circuit.

Here, the potential difference V h-a and the potential difference Vi-e are calculated using four bullets. The input signal is V, and the potential of turning on when unattended is V.
, the constant is k (constant), the potential vb of the point is Vb' = V-kv, and this causes the base-mitter voltage H- of the transistor Q2 to become VBE2. Assuming that the current of the constant current 13 is ■1, the electric potential vh is Vl)=-■-1<v-Ve E 2-R1・I+
(1), and the voltage across the terminals of diode D1 is Vo+
Then, the potential Ve at point e is Vc = v-kV-vB E 2-VD +
(2) Yell.

Similarly, the potential Vc of () and (') is VC=■-1kV, and if the voltage between the base and emitter of the transistor Q6 is VBE6.The current of the constant current source 4 is lc, the potential of the transistor i is is Vi = v+kv-Vs E 6-R2・r2 (3i, and if the voltage between the terminals of diode D2 is VC2,
The potential V(+ at point 9 is V(1=-V-LkV-VBEs-Vo2
(4) becomes.

From equations (1) and (4), the potential difference Vh-o is Vh-g
=V-kv-Va E2-R1・II -V-kV+Vs E 6 +VD 5 (5) Since Va E2 = Vs E6 is set, the formula 6) is Vll-(1=Vo 2 -R1・I +-2kV
, (6). On the other hand, from equation (2), (formula 31,
The potential difference Vi-e is Vi-e = V0kv-VB E
6-R2・I 2-V+kVjVs E 2 +VD
1 -VDI -R2・12 +2kV (7) Tonal. VD l =VD2, R+ ・II −R2・
Since they are set to I2, Va2-R+ lIt = Vo + -R2・I2-
When ΔV is set, equations (6) and (7) are as follows: V h−g−ΔV =2kv (
8) vie-e-ΔV+2kv (
9).

That is, Vh-a and (i-e) change in opposite phase and in phase, respectively, with respect to the input signal around the DC potential ΔV.

Here, Figure 113 <A> shows changes in the potential difference V11-Re (broken line) and the potential difference Vi-e (solid line) when a triangular wave with a period of 1- as shown in Figure 2 enters as an incoming horn signal. , the same figure (B) shows the transistor Ot+.

Q10] Rector current vs. potential difference yh-g, ■ie
Accept the characteristic diagram.

Transistors Qll and QI2 are Vh-o and Vi-
When c is less than about 0.7V, it is off and no collector current flows, but when Vll-(1, Vi-e exceeds about 0.1V, it is turned on and the collector current is Vh-c+, Vi
- τ changes linearly as e changes. Here V h
-g, Vte change as shown in the characteristics shown in the figure (A), the collector currents of the transistors Qn, Q+2 change as shown by the broken lines and solid lines in the figure (C), and the collector load resistance R3 , R4, the voltage at point 19 Vj, v+( changes as shown in FIG. 3D).

The voltages at the 12 points are applied via transistors Q13 and Q14, respectively. It is supplied to the differential amplifier composed of QIO and synthesized, and the signal is output from terminal 2 as shown in Fig. 3 (E).
As shown, the output horn signal sliced near the zero loss point is extracted.

At this time, the transistor Q II + 012 performs the slicing operation using the difference between the signal t, which is in phase with the input signal, and the signal d, which is in opposite phase, so the potential difference is twice that of the circuit shown in Figure 5. (That is, twice the signal amplitude as in the circuit shown in FIG. 5 is used.) This reduces the influence of the nonlinear region where the transistor goes from on to off by half. Therefore, when cutting an extremely small level relative to the signal amplitude, leakage of signals below the slice level caused by the nonlinear operation of the l range meta can be suppressed to a small level. Compared to the circuit shown in FIG. 5, it is possible to slice a small level signal more reliably, and even a low power supply voltage circuit can be sliced accurately.

The slice level setting is constant current 1+.

This is done by appropriately selecting the value of I2, and by changing it appropriately, the ΔV in equations 0 and (9) changes, the operating points of Vh-0 and Vi-e move, and the slice level is determined. Ru.

Furthermore, by reversing the direction of the constant currents 11.12 from those shown in the first diagram so that they flow into the point 11.1, it is possible to obtain a signal that emphasizes the small level portion.

That is, in FIGS. 3A and 3B, the order n of ΔV is the transistor QI1. As a result, in the portion where Vll-0 and Vi-e have small amplitudes, transistors QI+ and Q10 are both turned on and their outputs are taken out together, and this output is transferred to transistors Q9. Q1+
+, and the low level signal is extracted with twice the emphasis.

Modified Example FIG. 4 shows a circuit diagram of another embodiment of the circuit of the present invention, in which parts having the same functions as those in FIG. 1 are given the same numbers and their explanations will be omitted. This one is transistor Q2
, Q6 performs the slicing operation using signals in phase with and in phase with the input signal, and the circuit can be constructed more simply than that shown in FIG. Slice level is 13/2+I
Resistance Rs caused by 5 and (3/2+In, R7
It is determined by the DC voltage drop of

Effects As described above, the slice circuit according to the present invention includes a first transistor whose base is supplied with a signal that is in phase with the input signal, a second transistor whose base is supplied with a signal that is in opposite phase to the input signal, A constant current source is connected between the base and emitter of the first and second transistors and the ground, and a potential is applied to the emitter of the first transistor at a predetermined potential level shifted from the base potential of the second transistor. At the same time, a potential level-shifted by 71 with respect to the base potential of the first transistor is applied to the first transistor of the second transistor. Since the collector of the 1-range metal is configured with a circuit for amplifying and extracting the axle of the signal to be taken out, it can generally be constructed only with the range metal with good frequency characteristics. Also, since the first and second transistors perform a slicing operation using the difference between a signal in phase with the input signal and a signal in phase with it, the potential difference is twice that of the conventional circuit (i.e. (The signal amplitude is twice that of the conventional circuit), and in addition to this, the influence of the nonlinear region where the range meta changes from on to off is halved, and therefore the signal amplitude is extremely small. When cutting very small levels, leakage of signals below the slice level caused by the nonlinear operation of transistors can be suppressed to a minimum, and compared to conventional circuits, small level signals can be sliced more reliably, and the power supply voltage is lower. Even circuits can be sliced accurately, and circuits can be relatively cylindrical,
The external device does not require a capacitor, and has the advantage that by appropriately changing the direction of the current from the constant current source, it is possible to generate a signal that emphasizes the low level portion.

[Brief explanation of drawings]

1, 2, and 3 are respectively a circuit diagram of one embodiment of the circuit of the present invention and a signal waveform diagram for explaining its operation, FIG. 1 is a circuit diagram of another embodiment of the circuit of the present invention, and FIG. Figures and Figures 6 and 7
The figures are a circuit diagram of an example of a clip circuit previously proposed by the applicant and a signal waveform diagram for explaining its operation. 1...C1 input terminal, 2...signal output terminal, 3,
4... constant current source, Q+, Q2, Qs, Q6. Q
9-014...1 to 7 resistors, R1-R4, R6
, R7...Resistor, [)I, D2...Diode. Figure 4 Figure 3 → Figure 5 Figure 7

Claims (1)

[Claims] a first transistor whose base is supplied with a signal that is in phase with the input signal; a second transistor whose base is supplied with a signal that is in reverse phase with the input signal; and bases and emitters of the first and second transistors. and a constant current source connected between the base potential of the second transistor and a constant current source connected between the emitter of the first transistor and the ground; a level shift circuit that applies a potential level-shifted by a predetermined level with respect to the base potential of the first transistor to the emitter of the first transistor; A slice circuit characterized by comprising a circuit for amplifying and extracting a difference.