JPS623736Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a display device that displays signal levels using a plurality of light emitting elements. The object of this invention is to change the signal level into several levels to display the magnitude of the signal level depending on the brightness state, so that fine changes in the signal level can be displayed using a small number of light emitting elements.

Conventional audio equipment uses mechanical level meters of the moving coil type with a pointer to display the signal level, but recently devices have been used that electrically display the signal level by changing the number of light-emitting diodes arranged in parallel or the number of anode electrodes of a single fluorescent display tube that light up depending on the magnitude of the signal level. When using such a display device to display the magnitude of the signal, if you want to display the signal change in a finer scale, you will need a lot of light-emitting elements, which will increase the price, and in the case of devices that use dry batteries as a power source,
This also increases power consumption, which is undesirable.

In addition to changing the light-emitting element in two stages, turning it off and turning it on, the present invention changes the brightness of one light-emitting element in multiple stages when it is turned on, and changes in the signal level are converted into changes in the brightness of the light-emitting element. The present invention provides a simple device that can display finer changes in signal level without increasing the number of light emitting elements.

As an example, a display device in which three light emitting diodes are used and each light emitting diode changes in brightness in two levels will be described below with reference to the drawings.

FIG. 1 shows a circuit configuration of an embodiment of the present invention.
In the figure, a constant reference voltage Vs is applied to both ends of a series circuit of a plurality of resistors _R1 to _R6 . A plurality of voltage comparators A ₁ to A 6 are used to compare the voltage comparators A ₁ to _{A 6} in which threshold values are set in a level-ordered manner at the mutual connection points of each resistor X ₁ to X 5 and the reference voltage application point X ₆ of the resistor R 6. A reference voltage input terminal (negative side) is connected, and the signal input terminals (positive side) of these voltage comparators are connected in common, and a signal to be displayed is applied thereto. Further, in the constant current circuits _B1 to _B6 formed in a part of the voltage comparators _A1 to _A6 , _B1 is connected to _B2 , _B3 is connected to _B4 ,
_B5 and _B6 are each connected in parallel, and each is connected to the +B side of the power supply via light emitting diodes _D1 to _D3 . In the above voltage comparator, if the potential of the signal input terminal (positive side) is higher than the potential of each comparison reference voltage input terminal (negative side), current flows through the corresponding constant current circuit, and the light emitting diode connected to it flows. is starting to light up.

Now, if we consider the case where the input signal level increases sequentially, first, the potential of the input signal level becomes higher than the potential of the input terminal of the comparison reference voltage of voltage comparator _A1 (potential of point _X1 ), Constant current circuit B ₁
A current flows through, and the light emitting diode _D1 lights up.
Furthermore, the input signal potential increases, and voltage comparator A ₂
When the comparison reference voltage becomes larger than the input end potential (potential at point _X2 ), a current flows through constant current circuit _B2 , and this current flows through _D1 , so light-emitting diode _D1 lights up even brighter than before. state. In this way, as shown in Fig. 2, as the input signal becomes larger, a→b→c→d→e
→f→g, the states of the light emitting diodes _D1 to _D3 change, and seven states can be displayed with three light emitting diodes.

As explained above, according to the display device of the present invention, more signal levels can be displayed with the same number of light emitting elements, and a simple and effective display device can be provided.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is a diagram showing a lighting state of a light emitting diode according to the present invention. A ₁ - _{A 6} ... Voltage comparator, B ₁ - B ₆ ... Constant current circuit, D ₁ - _{D 3} ... Light emitting diode, R ₁ - R ₆ ... Resistor.

Claims (1)

[Scope of utility model registration request] A signal is applied to the input terminals of multiple voltage comparators with different comparison reference voltage values, and a light emitting element is connected to each output of these multiple voltage comparators via a constant current circuit to light up the multiple light emitting elements. In a device that displays an input signal level depending on the state, each constant current circuit connected to two or more voltage comparators having different comparison reference voltage values is added to a common light emitting element, and connected to the light emitting element. 1. A signal level display device, characterized in that the input signal level is displayed by changing the brightness of the light emitting elements stepwise by the number of constant current circuits.