JPS6150069A - Level display unit - Google Patents

Abstract

PURPOSE:To facilitate the reading of a signal level, by selecting a display control data memorized in memories with a data selector to enable a high resolution display without increasing the number of display elements. CONSTITUTION:An input data DIN digitized from an audio signal is supplied to a display control section 2. When a data selector switch 5 is set to select a memory 11, the control section 2 compares the input data DIN with a display control data D1 and the input data is shown on a level display section 3 with a resolution of 1dB when the input data is 0--10dB, with that of 2dB when it is -10--40dB and with that of 4dB when it is -40--60dB. When memories 12-17 are selected with the data selector 5, the data is displayed in a expanded scale with a resolution of 0.1dB centered on -10dB, -12dB, -14dB, -16dB, -18dB and -20dB.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a level display device that performs digital level display by selectively driving a plurality of display elements according to the signal level of an audio signal or the like. In particular, the present invention relates to one having a function of switching display resolution.

[Conventional technology]

In general, tape recorders use a level meter with an analog display using a V (J meter) or a level meter with a plurality of display elements such as light emitting diodes arranged to digitally display the input signal level as a bar graph. It is designed to display the signal level of the audio signal.

Conventionally, a level display device that displays a level digitally is shown, for example, in Japanese Utility Model Application No. 55-19322 (B converts an analog input signal into a digital signal, A device in which a plurality of display elements are selectively driven via a decoder is known. In this conventional example, a digital signal corresponding to a predetermined range of levels centered around a predetermined level is also auxiliary. It has a function of displaying the level of resolution by leveraging the decoder.

[Problems to be Solved by the Invention] In a level display device that performs digital level display by selectively driving a plurality of display elements according to the input signal level, the display range and display resolution vary depending on the number of display elements. There is a problem that if a group of display elements is used to display a wide display range (high resolution), the number of display elements becomes enormous. Even if a separate display element is provided for high-resolution display, an increase in the number of display elements cannot be avoided, which has the disadvantage that the device becomes too hot, and it is difficult to read the displayed signal level. There was a problem that it became inconvenient.

Therefore, the present invention provides the following advantages: without increasing the number of display elements;
It is an object of the present invention to provide a level display device with a novel configuration that enables high-resolution display, reduces the size of the device, and facilitates signal level reading.

[Means for solving problems]

In order to solve the above-mentioned problems, a level display device according to the present invention includes a level display section having a plurality of display elements arranged in parallel, and selectively driving the plurality of display elements according to an input signal level. a display control section for controlling the display of the level display section at a predetermined resolution, a memory for storing display control data for controlling the display of the level display section by the display control section at a predetermined resolution; The device is configured to include a memory that stores display control data for enlarging the vicinity of the signal level, and a data selector that selectively supplies the display control data read from each of the memories to the display control section.

[For production]

In the level display device according to the present invention, by selecting the display control data stored in each memory using the data selector, the display control resolution of the level display section can be switched, and the display control resolution can be changed around a predetermined signal level. Displays the level with an expanded scale.

〔Example〕

Hereinafter, one embodiment of the level display device according to the present invention will be described in detail with reference to the drawings.

The block circuit diagram in FIG. 1 shows an embodiment in which the present invention is applied to a level display device for a digital audio system. In this embodiment, 15 bits of audio input data DIN obtained by digitizing an audio signal is It is assumed that the signal is supplied from the signal input terminal 1 to the display control section 2.

The level display device of this embodiment includes 31 light emitting diodes Ll, L2 . . . , a level display section 3 having a level display section La, and seven memories 11, 12, 13 that store display control data Ds for controlling the display of the level display section 3 at different resolutions by the display control section 2.
, 14, 15, 16°1Y, and the seven memories 11.
a data selector switch 5 for selectively connecting one of 12, 13, 14, 15, and 16.17 to the display control section 2;
It consists of:

In this embodiment, the first memory 11 stores the signal level indicated by the audio input data DIN in units of decibels [dB] with a resolution of ldB ranging from OdB to -1.
Corresponding to 0dB, 2dB resolution -10dB to -4
Corresponding to QdB, -40dB to -6 with 4dB resolution
Display control data Dl as shown in FIG. 2A corresponding to 0 dB is stored. Then, the display control section 2
When the data selector switch 5 is set to select the first memory 11, the display control data D1 supplied from the memory 11 and the audio input data I)rN supplied from the signal input terminal 11 are , it is determined which level the signal level indicated by the audio input data DIN is in the range of QdB to -5QdB, and the 31 light emitting diodes L1 . L2, . . . , La are selectively emitted and driven. Here, if the audio input data DIN indicates a signal level of, for example, [262A] in hexadecimal notation, the display control section 2 controls the first
By comparing the display control data Dl read from the memory 11 with the input data DIN, the signal level [262A] indicated by the input data DIN becomes the signal level indicated by the display control data l)i. of [24
-1 Q corresponding to the range greater than or equal to [13] and less than [28 EO]
dB, the light emitting diodes Lll, L12, . . . of the level display section 3 are determined as shown in FIG.
・, La1 emits light.

In this embodiment, the second memory 12 also stores a range of -9,0 dB to -12,0 dB.
The above 31 light emitting diodes Ll with a resolution of B.

L2. . . , display control data D2 as shown in FIG. 2B, which corresponds to La1, is stored. This display control data D2 is obtained by enlarging the display scale in the range of 19 dB to -12 dB centered on 110 dB by display control based on the display control data D1 stored in the first memory 11. It is shown with a resolution of .1dB.

That is, the data selector switch 5 selects the second
If the memory 12 is selected, the above input data DI
The signal level [262A] indicated by N is -10.5 dB, which is greater than or equal to [25PE] and less than [:266F'] of the signal level indicated by the display control data D2 read from the second memory 12. is determined by the display control section 2, and as shown in FIG. 3B, the diodes Lio and Lu
, . . . are displayed by the light emission of La1.

Furthermore, in this embodiment, in addition to the above-mentioned vicinity of -10 dB,
-12dB, -14d13, -16dB.

Each display control take D3. as shown in FIGS. 2C to 2G for expanding the scale around the signal levels of -18 dB and -20 dB and displaying them with a resolution of 0.1 dB. D+, [ls.

Da, D7 as third to seventh memories 13, 14°15
．． 16.17, and by selecting each memory 12.13, 14, 15°16.17 with the data selector 5, it is possible to selectively enlarge and display the vicinity of six types of signal levels. be.

As in this embodiment, display control data D2 for expanding the display scale around a specific signal level in level display based on display control data Ih stored in the first memory 11, for example, -IQdB, is used as the second display control data D2. memory 12
If the display is controlled by reading data from the display element L1. L
z,..., without increasing the number of Lll, the above -
IQ dB vicinity can be displayed with a resolution of 0.1 dB. As described above, if the scale is enlarged and high-resolution display is performed around a specific signal level, the displayed contents can be easily read.Furthermore, in this embodiment, 1. The second to jth memories 12, 13, 14,
15.16. By selecting I C near, 6
Different signal levels namely -1 odB, -12 dB, -
x4dB, -! 16dB, -18dB, -20dB
Since the scale can be expanded in terms of translation,
The 31 light emitting diodes Ll, L2, . . . in the above level display section 3.

With La1, the level can be displayed over a wide range of -9.0 dB to -21.5 dB with a resolution of Q, 1ctI3.

In addition, in the above-mentioned embodiment, in the display control unit 2 41
, audio input data DIN and display control data Dl
, each light emitting diode Ll, L2+..., La1 of the level display section 3 is selectively emitted,
However, each light emitting diode 1,'
Ll, L2.

. . , look-up table data for selectively driving light for Lal is stored in a memory, and the look-up data is directly read from the memory using the input data DIN as an address to drive each light-emitting diode Ll, L2, . . . rL" may be selectively driven to emit light.

[Effects of the Invention] As is clear from the description of the embodiments described above, in the level display device according to the present invention, the display control data stored in each memory can be selected using the data select button, so that a specific display can be performed. Since the level display is performed with the scale expanded around the signal level, high-resolution level display can be performed without increasing the number of display elements in the level display section, making it easy to read the display contents. Miniaturization can also be achieved.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing an embodiment of the level display device according to the present invention, and FIGS. FIGS. 3A and 3B are explanatory diagrams schematically showing the contents of a display control take, and FIGS. 3A and 3B are schematic diagrams respectively showing examples of display by the level display section in the above embodiment.

Claims (1)

[Claims] a level display unit having a plurality of display elements arranged in parallel; a display control unit that performs display control to selectively drive the plurality of display elements according to an input signal level; and the level display unit by the display control unit. a memory for storing display control data for performing display control at a predetermined resolution, a memory for storing display control data for enlarging the vicinity of a predetermined signal level in a display control state at the predetermined resolution, and each of the above-mentioned memories. and a data selector that selectively supplies display control data read from the display control section to the display control section.