JPS6057249B2 - semiconductor bidirectional amplifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor bidirectional amplifier using semiconductor diodes.

The inventor has already proposed a unidirectional amplifier using semiconductor diodes. (Patent No. 68318) The breakdown phenomenon of a Zener diode and the punch-through phenomenon of a transistor are phenomena in which the internal resistance is drastically reduced, and moreover, these phenomena are resilient and immediately recover when the voltage is lowered.
Note that this operation is extremely fast and extends into the ultra-high frequency range.
The punch-through phenomenon of transistors is that both P-type and NPN transistors have different directions of positive and negative voltages applied between the collector and emitter;
The elephant itself occurs in much the same way. Figure 1 shows the load resistance R
A measurement circuit and its measurement results are shown for measuring the dynamic characteristics of a semiconductor diode D which is connected in series to a semiconductor diode D which causes the penetration phenomenon of an open-base transistor.

In Figure a, if the critical voltage for the breakthrough phenomenon due to positive voltage is Ec, then until the DC voltage reaches the critical voltage Ec, the internal resistance Rd of the semiconductor is extremely large, so that almost no current flows. When the voltage is raised to the critical voltage Ec, current begins to flow, and when the voltage is raised from Ec by ΔE, a current of I flows, and a voltage drop RI occurs across the load resistance R. Suppose that the internal resistance Rd of the semiconductor D up to the critical voltage Ec is infinite and the current is 1.
If is zero, the output voltage across R, that is, the voltage drop RI of R, is zero, and when the voltage is increased by ΔE from the critical voltage Ec, the semiconductor will cause a punch-through phenomenon,
Therefore, if the internal resistance Rd becomes zero, the voltage drop RdI becomes zero, and the voltage drop of R, that is, the output voltage becomes (Ec+ΔE). Therefore, assuming that the voltage amplification degree is A, A is calculated as follows. Ec to ΔE
As a result, the voltage drop of R, that is, the output voltage, increased from 0 to (Ec + ΔE), so ΔE
The smaller is and the larger is Ec, the larger is A.

The value of critical voltage Ec is (-20V) for Zener diode.
~50V), 80V~120V) in the positive direction punch-through phenomenon of transistors, and ΔE is (1~2)■
The degree is general. Generally, the relationship between voltage E and current 1 in a semiconductor is expressed as a non-linear relationship, and when voltage E is small, its internal resistance increases. Since E is large, current 1 is small, and as E is increased, internal resistance becomes smaller and current 1 increases.

Therefore, let the internal resistance be Rd, and Rd. When the relationship of l5l is actually measured and plotted on a graph, when I is small, Rd is large and I
As Rd increases, Rd suddenly decreases and becomes hyperbolic! A line appears and can be roughly expressed as (Rd=K/In). Here, K is a constant n, which varies depending on the type and variation of semiconductors (n
〉1). After the Zener diode breakdown phenomenon occurs,
After the penetration phenomenon occurs in transistor diodes with open bases, their internal resistance Rd decreases significantly, so the value of n is large. In the circuit shown in Fig. 1a, when the DC voltage is successively increased above the critical voltage Ec for the breakthrough phenomenon, I also increases, and as a result, the internal resistance Rd sharply decreases to a hyperbolic shape approximately TvJLLI, and the voltage drop across the semiconductor. ■d decreases according to Ohji's following formula.

Eventually, the current 1 increases due to the drastic decrease in Rd, and the load resistance R
voltage drop increases.

Therefore, the voltage drop across the semiconductor is 0, and when the relationship with Vd<51 is measured and plotted on a graph, it becomes a current-controlled negative resistance curve as shown in FIG. 1b.

When the power supply voltage is further increased, the negative resistance characteristic of the semiconductor is lost and many become normal ohmic resistance. However, depending on the variety, this negative effect may occur. The voltage range of the resistor is (50
V to 80 V) or more. Negative resistance can constitute an active circuit and can cause loss of oscillation and amplification. Moreover, since the voltage range of the current negative resistance after this punch-through phenomenon occurs is wide, the output is large, and the speaker can produce high-pitched sound. (In the case of an Ezaki diode, when the DC voltage applied to both ends is increased by 2 to 3 V, carriers penetrate through the depletion layer and movement of carriers occurs. As a result, the internal resistance increases and the current decreases. It has a negative resistance of , but its voltage range is 0.4■ or less and the output is small.
The speakers hardly make any sound.

) FIG. 2a shows a basic circuit of a semiconductor bidirectional amplifier according to the present invention, which utilizes a negative resistance after the punch-through phenomenon of an open-base transistor diode occurs.

FIG. 2b is a temporary diagram provided to clarify the operation, and shows the upper half of FIG. 2a. In FIG. 2, it is assumed that a high current voltage EB is applied after the punch-through phenomenon occurs, and a current is flowing. Therefore, the internal resistance Rd of the semiconductors D1 and D2 is roughly inversely proportional to P as shown in the above equation (Rd=K/I''). In FIG. 2b, when a positive voltage is applied to the terminals 1 and a, Therefore, the current 11 flowing through D1 increases, and therefore the internal resistance of D1 decreases greatly.Since the power supply voltage EB is equal to the sum of the voltage drops of Rl, Dl, and R3, an increase in 11 causes the internal resistance of D1 to decrease. is greatly reduced, and therefore, if the voltage drop of D is reduced, the sum of the voltage drops of R,, R3 will increase by that reduction.R3
Since the voltage drop is equal to the output voltage between 2 and a'' in figure b, as a result, when a positive voltage is applied between 1 and a, the output voltage between 2 and a'' increases. In this case, the internal resistance of D1 decreases significantly, so an output voltage greater than the value of the positive voltage applied between 1 and a is generated between 2 and a''.Next, a negative voltage is generated between 1 and a. When 11 is added, 11 decreases, so the internal resistance of D1 becomes significant, and therefore the voltage drop of D1 becomes significant.
Since the sum of the voltage drops of Rl, Dl, and R3 is equal to EB, if the voltage drop of D1 becomes significant, the sum of the voltage drops of R1 and R3 will decrease by that amount, and the voltage drop of R3, that is, the output The voltage decreases. Since the change in the internal resistance of the semiconductor after the punch-through phenomenon occurs is extremely large, the output voltage between 2 and a'' can be made larger than the input voltage applied between 1 and a, and the phase of the output voltage is equal to the input voltage. This time, when a positive voltage is applied between 2 and a'', 11 decreases, so the internal resistance Rd of D1 increases dramatically.

Since EB is equal to the sum of the voltage drops of Rl, Dl, and R3, as the internal resistance Rd of D1 increases, the internal resistance increases and the voltage drops of R1 and R3 decrease. In this case, the voltage drop across R1 becomes the output, so the right side 2,a
When a positive voltage is applied between ``2'' and ``a'', the voltage drop across R1, that is, the output voltage decreases, and the phase becomes opposite to the positive voltage between 2 and a''. 2,
When a negative voltage is applied between a'', R2 and ll become smaller, and 11 increases sharply.As a result, the internal resistance of D1 sharply decreases, and the voltage drop of D1 also sharply decreases, and the sum of the voltage drops of Rl and R3 becomes Since the output voltage increases dramatically, the output voltage between 1 and a increases dramatically in opposite phases.

Figure 2a shows a practical basic circuit with the lower half added to Figure 2b, and the lower half acts on the operation of the upper half in an antiphase manner, resulting in the result shown in Figure b. Exhibits double amplification effect.

Considering the reason, it is now assumed that Dl and D2 have exactly the same characteristics, and the values of R1, R2, R3, and R4 are also completely equal. When a positive voltage of 10V is applied between Rl and R2, a voltage of 5V is applied to each of Rl and R2.

Since the voltage of 5V applied to R1 is in the same direction as the voltage of the power source EB and both are added together, the current 11 increases, and the increase is defined as ΔI. The 5V applied to R2 acts in the opposite direction to EB, and D2
The voltage applied to is (EB-5V) and the current is (1
The output voltage between 2 and 2" becomes (2 - ΔI) before adding 10 seconds between 1 and 1", (11=12), and assuming (R3=R,), it becomes (R3ll-R, l2=0 ). 1
This is because 1 and 12 flow in opposite directions.

When 10V is applied between 1 and 1″, R3(11+ΔI)−R
4(12-ΔI)=R2Δ1+R,ΔI), and (R
3=R4), the output will be twice that in the case of only the upper half.

Its phase is equal to the phase of the input. Amplification is performed because the internal resistance changes significantly with respect to the currents of Dl and D2. A case in which a negative voltage is applied to 1, 1'', a case in which an input is applied from 2, 2'', etc. are similarly considered.

However, when input is applied to 2, 2'', the output to 1, 1'' will be in opposite phase. The circuit shown in FIG. 2a is completely symmetrical and exhibits a stable amplification effect by mutually canceling out self-oscillation due to negative resistance.

The values of the two resistors Rl and R2 are made equal, and the values of the other two resistors R3 and R4 are also made equal, Rl, R2 and R3, R4.
By making the resistance values different between the 1,1'' side and the 2,2'' side, the outputs can be made different.

An example of a practical circuit of the basic bidirectional amplifier circuit shown in FIG. 2 is shown in FIG.

This circuit uses capacitance for coupling with the input terminal, but
It is also possible to use a transformer. Frequency characteristics, linearity, distortion factor, and other characteristics are good and are on the same level as vacuum tube/transistor amplifiers.The amplification degree varies considerably depending on the type of semiconductor diode, but the current amplitude amplification degree is up to 1C@ It is about 2 to 2CPi. The voltage of the DC power supply EB in FIG. 3 also varies depending on the type of semiconductor diode, but the maximum voltage is about 250V. This can be easily obtained from AC 100V using a voltage doubler rectifier circuit, and is therefore transformerless, and since it is a symmetrically connected amplifier,
Even if the smoothing circuit is simple, no hum will appear in the output, and the sound quality will be good. In the case of open-base transistors and diodes, both Pnp and npn have two Pn or Np connections, so even if the positive or negative direction of the DC power supply is turned, a penetration phenomenon occurs and the function of a bidirectional amplifier is achieved. . However, in the case of a Zener diode, a DC power source in the opposite direction is used. FIG. 4 is a system diagram when these amplifiers are connected in tandem, and the purpose of this is to obtain a required gain by using it when the amplification level is insufficient with only one stage.

In the figure, 1 and 2 respectively indicate the bidirectional amplifier of the present invention. As described above, the present invention utilizes the current-controlled negative resistance of a semiconductor diode at a voltage higher than the voltage at which the breakdown phenomenon or punch-through phenomenon occurs in a bidirectional amplifier.

A bidirectional amplifier is an amplifier that has never existed before, does not require a control electrode, has a simple circuit, and it is expected that excellent semiconductor diodes suitable for this circuit system will be developed in the future, and it will also be effective in IC design. Become.

[Brief explanation of drawings]

The drawings illustrate the principles and embodiments of the invention. Fig. 1 shows a characteristic measurement circuit and the dynamic characteristics of the measurement results when a load resistor R is connected to a semiconductor diode that causes a breakdown phenomenon or a breakthrough phenomenon, and Fig. 2 shows the basics of a semiconductor bidirectional amplifier according to the present invention. FIG. 3 shows a circuit of an example of its application, and FIG. 4 shows a system diagram in which the amplifiers are connected in tandem. Note that EB is a DC power supply, Rd is an internal resistance of a semiconductor diode, Ec is a critical value of breakdown voltage or breakthrough voltage, and D, Dl, and D2 are semiconductor diodes.

Claims (1)

[Claims] 1. After the first input/output terminal pair 1, 1' undergoes a surrender phenomenon or a breakthrough phenomenon, its internal resistance Rd is approximately inversely proportional to the n-th power of the current, and (Rd=K/I A semiconductor diode D having the characteristic (n>1) when approximated to ^n)
The semiconductor diode D_1 is connected to one electrode of the semiconductor diode D_1, D_2, and the second input/output terminal pair 2, 2' is connected to the other electrode of the semiconductor diode D_1, D_2.
, D_2 are connected to one pole of a DC power source E_B via first resistors R_1, R_2, and the other electrodes of the semiconductor diodes D_1, D_2 are connected to a second resistor R_3, D_2.
A semiconductor bidirectional amplifier connected to the other pole of the DC power supply E_B via R_4. 2. The semiconductor bidirectional amplifier according to claim 1, wherein the power supply voltage value of the DC power source E_B is set to a value higher than the voltage that causes the breakdown phenomenon or breakthrough phenomenon of the semiconductor diodes D_1 and D_2. 3 First resistance R_1, R_2 and second resistance R_3, R
The semiconductor bidirectional amplifier according to claim 1, wherein the values of _4 are the same. 4 First resistor R_1, R_2 and second resistor R_3, R
The semiconductor bidirectional amplifier according to claim 1, wherein the values of _4 are different. 5 First and second input/output terminal pair 1, 1'; 2, 2'
through the capacitor C to the first and second input/output 1, 1'; 2
, 2'. 6 Connect the first input/output terminal pair 1, 1' to one electrode of the semiconductor diodes D_1, D_2, and connect the second input/output terminal pair 2, 2' to the other electrode of the semiconductor diodes D_1, D_2. and the semiconductor diode D_1,
One electrode of the semiconductor diode D_2 is connected to one pole of the DC power source E_B via the first resistor R_1, R_2, and the other electrode of the semiconductor diode D_1, D_2 is connected to the second resistor R_3, R_2.
2. The semiconductor bidirectional amplifier according to claim 1, comprising two or more sets of semiconductor bidirectional amplifiers connected to the other pole of the DC power supply E_B via the wire _4 and connected in tandem.