JPS5827563Y2 - IC control circuit - Google Patents

Description

[Detailed description of the invention] The present invention is based on an IC circuit that inverts the output binary state of high level and low level every time an input signal is input to the input terminal. It relates to a circuit that controls the results.

When the IC circuit is used for channel switching in a television receiver, for example, two input signals are required to perform one channel shift, which is inconvenient.

Therefore, it is necessary to take measures such that one input signal is required for one channel shift.

The present invention proposes an IC control circuit incorporating such a device.

In Fig. 1, 1 is the above-mentioned IC circuit, and when a low level input signal is applied to the input terminal 2, the output of the output terminal 3 changes from low level to high level, and then a low level human input signal is input. When applied to terminal 2, the output state is inverted and returns from high level to low level.

In this manner, the output state is inverted each time an input is applied.

Reference numeral 4 denotes the input signal generating means, and in the figure, it is formed as a switch that applies low-level human power to the input terminal 2 when closed, but it is also possible to use the IC circuit 1 for switching channels of a television receiver. When used, it consists of certain input signal amplification circuits and the like.

Ro is a resistor inserted between the output terminal 3 and the power supply +vcc.

5 represents the first and second transistors TrltTr2, their associated capacitors C1 and C2, and resistors R1tR2+R3,
It is an astable multivibrator consisting of R4, etc., and oscillates at a sufficiently small period compared to the input signal period, and the base of the first transistor Tri is connected to the output terminal 3 of the IC circuit 1 via a resistor R3. , is controlled by the output of the output terminal 3.

The pace of the second transistor Tr2 is directly coupled to the power supply +vccVc via the resistor R2, and the collector is coupled to the switching element 6 to control the switching element 6.

This switching element 6 is inserted between the input terminal 2 and a reference potential point, and is connected to the astable multivibrator 5.
The output terminal 3 is controlled to be on/off by a signal from the input terminal 3, and the output terminal 3 is set to a low level immediately after the input signal period has elapsed.

FIG. 2 shows another embodiment of the present invention, in which there are first and second input terminals 2a and 2b, and these input terminals are connected inside the IC circuit 1. 1
An input signal is given to the input terminal 2a, and the second input terminal 2b
[Switching transistor Tr3 is connected as shown.

Now, to explain the operation using the one in Fig. 2 as an example, when the state of the output terminal 3 is low level, the first transistor Trl is off and the second transistor Tr□ is on.
However, when an input signal (low level) is input to the first input terminal 2aVC as shown in Figure 3A, the output terminal 3 becomes... level (see Figure 3), so the astable multivibrator 5 starts oscillating.

FIG. 3C shows the level state of the second input terminal 2b that changes as the switching transistor Tr3 is controlled on and off by the oscillation output.

FIG. 32 shows the voltage waveform at the connection point in the IC circuit unit of the first and second input terminals 2a and 2b, which corresponds to the waveform at the input terminal 2 in FIG.

During the input signal period, the input signal is at low level, so the level at the connection point is low regardless of the level state at the second input terminal 2b, and the high level state at the output terminal 3 does not change, but the human input signal Immediately after the first input terminal 2a reaches the NO level, the third input terminal is connected to the connection point.
As shown in FIG. 2, one low level portion sandwiched between the high level portion H1tH2 always occurs.

This low level portion causes the output terminal 3 of the IC circuit engineer to return to the low level (initial state).

In this way, according to the control circuit of the present invention, when an input signal is applied to the IC circuit, the IC circuit outputs a negative state (e.g., low level), but it automatically returns to the previous state (e.g., low level). One output is obtained in response to one human input signal.

Therefore, no problem will occur even if an IC circuit whose output is inverted every time an input signal is input is used to generate shift pulses for channel switching.

Furthermore, according to the present invention, the input signal period returns to the initial state immediately after the input signal period ends, and does not return during the human input signal period.
For example, while the input signal generating means 4 is operating in FIG. 1, the output terminal can be kept at the 11 level, and the subsequent circuit (not shown) connected to the output terminal 3 is operated during this time. It can also be used for other purposes.

The present invention is extremely useful. In addition, when using the circuit for channel switching of a television receiver, the first input terminal is connected to the output terminal of the remote control signal receiving amplification circuit, and the output terminal 3 is connected to the ring counter of the selection device. It's good to do that.

Incidentally, when the circuit of the present invention is used in this 54C mode, an example of the values of the constituent elements of the astable multivibrator 5 and the elements used in the IC circuit 1 and the switching transistor Tr3 will be shown below.

IC circuit 1...SN76730 Transistor Tr3...2.5C536 astable multivibrator T"ri......2SC536T
r□・・・・・・・・・2SC536c1. c2
・・・・・・・・・0.047μFR1+ R4・・・
...56, ΩR2, R3...5
Ω resistor R5 at 60, Ω resistor R at 56, IOKΩ+Vcc ・
......+4.5 ■The oscillation frequency of the astable multivibrator 5 was 32 Hz, and its duty ratio was optimally 60%.

[Brief explanation of drawings]

The diagrams are all related to the present invention; FIG. 1 is a circuit diagram of an IC control circuit implementing the present invention, and FIG. 2 is a circuit diagram showing another embodiment. FIG. 3 is an explanatory diagram of the present invention. 1...IC circuit, 2...input terminal, 3
...Output terminal, 5...Astable multivibrator, 6...Switching element, Trl
, Tr2...transistor constituting an astable multivibrator, Tr3... switching transistor.

Claims (1)

[Scope of utility model registration request] An astable multivibrator is configured in which the output terminal of an IC circuit that inverts the binary state of high level and low level of the output every time an input signal is input to the input terminal oscillates at a cycle sufficiently smaller than the input signal period. It is connected to the control electrode of one transistor, and the output from the output electrode of the other transistor is used as a control signal for a switching element inserted between the input terminal and a reference potential point, and the output of the IC circuit is set to one of the above two values. When the predetermined one state changes to the other state, the multivibrator operates to drive the switching element on and off, and immediately after the input signal period has passed, the output of the IC circuit returns to the one state. An IC control circuit characterized by: