JPS60142278A - Inspecting device of led level meter unit - Google Patents

Abstract

PURPOSE:To inspect automatically a display function at a high speed by detecting the power consumption of an article to be inspected and a standard non- defective article, comparing a current difference of a corresponding display LED, and discriminating whether said article is good or not. CONSTITUTION:A standard non-defective article 2 of the same structure as an article to be inspected 1 is prepared, and both the articles are made to execute the same display driving by a power source circuit 3. Current detecting circuits 4, 5 detect the current consumption of both the articles, respectively, detect the difference of both currents by a differential circuit 6, and this value is held by a sample holding circuit 7. A differential circuit 8 detects the difference of the holding contents of the circuit 7 and an output of the differential circuit 6. A comparing circuit 9 compares the output voltage of the differential circuit 8 and a reference voltage 10, and when both the voltages coincide with each other, a coincidence detecting signal is sent out.

Description

[Detailed Description of the Invention] Technical Field> The present invention uses a plurality of L F,
Display device with D (solid state generation diodes) arrayed and its 0)
L made by mounting 1-life IC on the same board
E D Level Meter r-Knit inspection device 1W Regarding L, especially inspection of finished products stored in containers ↑t-,
'Regarding W placement.

Problems to be solved〉 For those that have not yet been stored in the case (with the Zunawara display and Triso River IC mounted on the ground on the base 4), it is difficult to use the probe on the C5L printed wiring pattern. It is possible to perform various inspections by providing a runt and using a contact pin to lead out the position of the current ζL E I) to the outside of the board.

However, even if the finished product is inspected without removing the cover case, the method described in -1- cannot be used to detect the deviation.

() After L, I looked at the examination table and 11. The display must be changed to the extent that the stippling of I (, l) can be used to determine the month of miscarriage, or the examiner's vision can be tracked.The time required will be increased, and moreover, there will be erroneous recognition. There was a problem with reliability because there was a risk of

<Object of the Invention> The object of the present invention is to provide a public power station which automatically tests the display function at a speed of 11-F without removing the cover case of the finished product.

<Configuration of the Invention> The I-, JE +) level make unit inspection device of the present invention includes a standard non-defective product having the same structure as the product to be inspected, and a current detection circuit that detects the power consumption of the product to be inspected and the standard non-defective product. , one L stage that detects the output difference between the two current detection circuits, and a comparison means that determines whether the difference is within a predetermined range or not. Each L of good quality
1. Corresponding to the back R of F, I). I, myself
The present invention is configured to compare the difference between the two currents at the time of 1) and 1) to determine whether the product to be inspected is good or bad.

<Example> Figure 1B1 shows a small system block diagram of an embodiment of the present invention.

A mark with the same structure as the test sample 1 (using good quality product 2 7Q:
The same display H51g was issued to both cities using the device power supply circuit 3. The current detection circuits 4 and 5 detect the current consumption of the inspected product ■ and the 1-vote semi-defective product 2, respectively, and the differential circuit il'6
6 detects the difference between both currents. Sample Bold episode (Raku 7)
The differential rotation of the ladder maintains the output of 1/8 fi.

The second differential circuit 8 detects the difference between the contents held by the lean-pull bold circuit 7 and the output of the differential circuit 6. The comparison circuit 9 compares the output of the differential circuit 1188 and the base 1 (t-X front pressure) 0, and outputs a coincidence detection signal if the two voltages do not match.The system control section 11 controls the entire device. ing.

In Figure 2, the action of the system shown in ``-'' is shown as i4<'J-0.
+,);:at] is -14. The current of the inspected product 1 at this time is Icc (s).

+4N〆((The current of good product 2 is I C (: (M). The sample vault circuit 7 calculates the difference between these two IM currents ΔIC (: (Ilold) - 1cc (s) Ic
e U ) to (lol) (ST2).

Next question, test subject 1! "Goods 1 and marks (1 (good products 2 people's jealousy 1
The human power level Vin applied to the child is sequentially changed. 1 of the current month according to the size of this input terminal Vin. ．． E
1. ) (1 ri 1161 number changes.4) L,
[I, G] When the IJ is defective, the current consumption value will decrease compared to the old condition. First of all, let's start with the 11th No. 1 for U7.
l': 1. ) The input voltage Vin is applied so as to light up the eyes. The output of the first differential circuit 6 when C is Δl (:C1= lcc (s) −1cc (M
) There is. The second differential circuit 6 is the difference Δic between the current ΔIcc1 and the bold electric current ΔIcc, (llold).
c] -Δ1cc1-Δl cc (flood) is detected (S'r5). Next, the comparison circuit calculates the Δ!
cc'l is within the specified tolerance range, but the stand is 14J
``Yes (ST6), if it is in flfijlftl, proceed to Zoranna (7,) ST
:3, the input terminal Vin changes to the next value, and the same test is repeated. When this inspection is completed for ZUBE'ζ0 old 2 no I, ST7 is YES, and the entire inspection is completed. In judgment step sT6, if the talent is within the range (j'l is judged as 14Ii), then S
Tl+”, advance, “NoGO” is displayed, test f1
Or end 1゛'Jru.

Figure 3 shows a circuit diagram of an embodiment of the present invention -4゜Inspected product 1
No., 1.12 f1MIθ month-E l) I) +-0
12 are arranged in a line and connected to the blade terminals 0UT1-OUTl2 of the driver ICQI. Each LED uses the voltage applied to the Vref terminal as a reference voltage, and
It lights up in response to the input terminal Vin applied to the jr++4 child. The current flowing through the LED is controlled by a resistor R to have a constant current value. Current detection circuits 4, 5 are connected between device application power source 3 and level meter unit 1.2. The first and second differential circuits 6.8 are operational amplifiers Q3
．． It is composed of Q5. AN, D gate circuit Q6
In synchronization with the synchronization signal of the control section 11, the comparator circuit 9 outputs a mismatch "a'+zunawara NoGo'" signal.

<Effects of the Invention> According to the present invention, each and every display state can be completely automatically inspected by visual inspection, so that the inspection viscosity and reliability are improved. Furthermore, since the display state can be switched to iI'IJ speed, inspection time is shortened.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a flowchart 1 showing the operation of the embodiment described above, and FIG. 3 is a circuit diagram of the embodiment described above. 1. Tested by him 2-Standard non-defective product 4.5--'iii flow detection flow path output circuit 9-Comparison circuit 1 Within the patent attorney 1) New hand *-yi-? c city positive concave: (spontaneous) 2. Name of the invention L E Test word for one level meter unit Fit3,
Name of person making the correction (504) Sharp Corporation Representative Saeki Asahi 4, Agent address 15-13-6, Usagano-cho, Kita-ku, Osaka, ? di positive object bright, fn + book

Claims (1)

[Claims] This is an inspection device for a device that arranges a plurality of 111 + 1-, EI) in a predetermined pattern and produces a number of LE I') corresponding to the input signal. = record failure + * A current detection circuit that detects the extinguishing power of the crystal and the standard non-defective product, a means for detecting the output difference between both rh flow detection circuits, and whether the difference is within a predetermined range. It has a comparison means for determining whether the above-mentioned inspected product and -
Compare the difference in flow between each L E l) corresponding to the back Jl- of the standard non-defective product described in 7, and determine the food table of the inspected product. L E L
) Level meter unit M interposition FR0