KR0176507B1 - Pcb test/control system for camcorder - Google Patents

Abstract

The present invention relates to a system for automatically checking and adjusting the electrical characteristics of a printed circuit board (PCB) for a camcorder, comprising: a processing apparatus for performing overall control and showing the result; A video signal generator motor for generating predetermined signals and a trigger signal generator; And a radio frequency signal generator; A selection circuit unit for selectively outputting predetermined signals; A signal processor which processes signals input from the selection circuit; It is possible to provide an automatic inspection-adjustment system capable of not only using the deck of the video cassette recorder but also inspecting-adjusting the digital signal.

Description

System for checking and adjusting circuit boards for camcorders.

1 is a schematic block diagram of a system for inspecting-adjusting a circuit board for a camcorder according to a conventional method.

2 is a block diagram of a system for inspecting and adjusting circuitry for a camcorder according to the present invention.

3 is an internal block diagram of the motor and trigger signal generator of FIG. 2.

FIG. 4 is a schematic diagram of the second selection circuit part of FIG.

5 is an internal block diagram of the digital signal processor of FIG.

* Explanation of symbols for main parts of the drawings

1a: VTR deck 1b, 2g: video signal generator

1c, 2i: radio frequency signal generator 1d: selection circuit

le, 2r: Circuit board to be measured 1f: Fixture

1g: TV 2a: personal computer

2b: keyboard 2c: monitor

24: printer 2e: GPIB interface

2f: Power supply 2h: Motor, trigger signal generator

2j: first selection circuit portion 2k: second selection circuit portion

2l: digital signal processor 2m: signal amplifier

2n: analog signal processing unit 2o: frequency measuring unit

2p: motor drive part 2q: motor for adjustment

3a: vertical synchronous signal separation circuit 3b: programmable counter

3c: latch circuit part 4a, 5a: interface

4b: 3rd buffer 4c: 1st relay part

4d: second relay unit 4e: third relay unit

4f: fourth relay part 4g: fifth relay part

4h: first buffer 4i: second buffer

5b: maximum value circuit section 5c: minimum value circuit section

5d: digital signal processing-integrated circuit section

The present invention relates to a system for automatically checking and adjusting the electrical characteristics of a printed circuit board (PCB) for a camcorder. The camcorder functions as a video camera and a video tape recorder (VTR). Say the product together.

FIG. 1 is a schematic block diagram of a system for inspecting and adjusting a circuit board for a camcorder according to a conventional method. In FIG. 1, la generates a motor signal of a predetermined specification while playing a video tape. Is a deck of video tape recorders. 1b is a video signal generator that generates a video signal of a predetermined specification. 1c is a radio frequency signal generator (RF signal generator) for generating radio frequency signals of predetermined specifications using the video signal. 16 is a selection circuit unit for selectively supplying the motor signal, the video signal, and the radio frequency signals according to the request of the inspector-regulator. le is a circuit board for a camcorder (DUT: Device Under Test) to be subjected to inspection-adjustment according to the signal supplied from the selection circuit section. 1f is a fixture for fixing the circuitry for the camcorder. And 1g is a television displaying an image in accordance with the output signal of the circuit board for the camcorder. The inspector-adjuster adjusts the variable resistor (VR) of the circuit board for the camcorder until it reaches the prescribed state while watching the reproduction state of the television. If it is judged that the optimum state is achieved by adjusting the variable resistance of the circuit board for the camcorder, the inspection-adjuster determines whether the product is passed or not based on the reproduction state of the image shown on the television.

The conventional screw-adjustment system as described above has the following problems.

First, as the inspection-adjuster manually adjusts the circuitry for the camcorder and visually checks the quality, not only the inspection accuracy is lowered but also the quality level of the product is not uniform.

Secondly, as the deck (la) of the video cassette recorder is directly applied, the time required for reproducing the tape becomes long and productivity is lowered.

Third, only inspection-adjustment for analog signals is possible, and inspection-adjustment for digital signals is not possible.

The present invention was devised in view of the above problems, and an object thereof is to provide an automatic inspection-adjustment system capable of not only applying a deck of a video cassette recorder but also inspecting-adjusting a digital signal.

The present invention for achieving the above object is a processing device for performing the overall control with suitable software and hardware (Hardware) and showing the results;

A video signal generator for generating a video signal according to a control command of the processing device;

A motor and a trigger signal generator configured to generate a predetermined motor signal and a trigger signal using the video signal;

A radio frequency signal generator for generating a radio frequency signal during play back using the video signal and the motor signal;

A first selection circuit unit for selectively inputting the video signal, the motor signal, and the radio frequency signal to a circuit board for a camcorder;

A second selection circuit section for selectively outputting various signals output from the circuit board for the camcorder to be inspected;

A digital signal processing unit for processing the digital signal input from the second selection circuit unit to perform a necessary operation and transmitting the result to the processing apparatus;

A signal amplifier for amplifying or attenuating the analog signal input from the second selection circuit unit;

An analog signal processor for measuring characteristics of an analog signal input from the signal amplifier and transmitting the measured data to the processing device;

An electric motor driving unit capable of driving the electric motor by a control command of the processing apparatus;

And a motor for adjusting and adjusting a variable resistor on the circuit board for the camcorder by the motor driving unit.

It characterized by including.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of a system for automatically checking-adjusting a circuit board for a camcorder according to the present invention. In FIG. 2, 2a is a personal computer adapted to a processing unit that performs overall control with suitable software and hardware and displays the results. 2b is a keyboard for inputting external data relating to the operating mode of the personal computer. 2c is a monitor that displays the output of a personal computer. 2d is a printer that prints output data of a personal computer. 2e is a General Purpose Interface Bus (GPIB) interface. 2f is a programmable power supply for supplying power to a circuit board for a camcorder according to a control command of a personal computer. 2g is a video signal generator that generates a video signal according to the control command of the personal computer. 2h is an electric motor and a trigger signal generator for generating a predetermined motor signal and a trigger signal using the video signal. 2i is a radio frequency signal generator that generates a radio frequency signal during play back using the video signal and the motor signal. 2j is a first selection circuit section for selectively inputting the video signal, the motor signal, and the radio frequency signal to a circuit board for a camcorder. 2k is a second selection circuit section for selectively outputting various signals output to the circuit board for the camcorder to be inspected. 2i is a digital signal processing unit which processes the digital signal input from the second selection circuit unit and inputs the processed data to the personal computer. 2m is a signal amplifier for amplifying and outputting an analog signal input from the second selection circuit. 2n is an analog signal processor that processes the analog signal input from the signal amplifier and inputs the processed data to the personal computer. 2o is a frequency measuring unit for measuring the frequency of the analog signal input from the signal amplifier and inputting the measured data to the personal computer. 2p is an electric motor drive part which can drive an electric motor by the control command of a personal computer. 2q is an electric motor for adjusting by turning the variable resistor on the circuit board for camcorder by the electric motor drive unit. And 2r is a circuit board for the camcorder to be subjected to automatic inspection-adjustment.

3 is an internal block diagram of the motor and trigger signal generator of FIG. 2. In FIG. 3, 3a shows a vertical synchronous signal separation circuit for separating and generating the vertical synchronous signal included in the video signal output from the video signal generator 2g; 3b is a drum motor signal (DPG DfG), a capstan motor signal (CPG 3, CFG), and a trigger signal according to the control signal of the personal computer 2a and the vertical synchronization signal. a programmable counter for generating a trigger signal; And 3c is a latch circuit unit for generating a deck switch signal in accordance with the control signal of the personal computer (2a).

FIG. 4 is a schematic diagram of the second selection circuit part of FIG. 4a is an interface for generating signals of a specified specification according to a control signal of the personal computer 2a: 4b is a digital signal Dl (1) from the circuit board under measurement 2r. A third buffer which receives .Dl (N) and outputs a digital signal DS having a specification according to a clear signal from the interface 4a; 4c (first relay section), 4d (second relay section), 4e (third relay section), 4f (fourth relay section), and 4g (five relay section) control signals from the interface 4a. A relay section for controlling analog signals S1 (1) ... SI (N) from the circuit board under measurement 2r according to the present invention; 4h (first buffer) and 4i (second buffer) are buffer sections for converting the analog signals into signals of a specified specification.

Referring to FIG. 4, the operation of the relay unit will be described with reference to the control signal from the interface 4a.

First, when the SI (1) is selected and measured from the analog signals from the circuit under test 2r, RY1 of the first relay unit 4c is turned on and connected to the contact A. The RY3 of the second relay section 46 is connected to the contact A when the magnitude of the input signal SI (1) exceeds a predetermined limit, otherwise it is connected to the contact B. When RY5 of the third relay portion 4e is connected to the contact A, and when RY7 of the fourth relay portion 4f is connected to the contact A, Vb is output through the second buffer 4i and connected to the contact B. Va is outputted through the first buffer 4h. For example, if the resistor Rl is set to 9 kW and R2 is 1 kW, and the variable capacitor C is connected in parallel to the resistor R1, a typical 10: 1 probe ( can be used as a probe).

When the input signals SI (1) and SI (2) are simultaneously measured, for example, when the two signals are output at the same time to measure the phase difference between SI (1) and SI (2), the fourth relay unit 4f ) RY7 is connected to contact B and RY8 is connected to contact A.

When measuring the input signal SI (1) When it is necessary to input the input signal SI (2) as a trigger signal to the I terminal of the analog signal processing section 2n, the RY2 of the first relay section 4c is contacted. A to RY4 of the second relay section 4d to para contact A or B to the magnitude of the signal, RY6 of the third relay section 4e to contact point A, and RY8 of the fourth relay section 4f to contact point A. The RY10 of the fifth relay portion 4g may be connected to the contact B. That is, the input signal SI (f) is outputted as Ve through the second buffer 4i and is input as a trigger signal to the E terminal of the analog signal processor 2n.

When the input signal SI (1) is not measured, the circuit board 2r to be measured is connected by connecting RY1 of the first relay portion 4c to the contact B and RY5 of the third relay portion 4e to the contact B. Do not input high frequency signal into the buffer part.

When the trigger signal output from the motor of FIG. 2 and the trigger signal generator 2h is input to the E terminal of the analog signal processor 21 as a trigger signal, the RYll of the fifth relay 4g is connected to the contact B. FIG. Just do it.

5 is an internal block diagram of the digital signal processor of FIG. 5A is an interface for generating signals of a specified specification according to a control signal of the personal computer 2a. 5b is a maximum value circuit section for sequentially storing a maximum value of an input digital signal. A minimum value circuit part which sequentially stores the minimum value of the input digital signal; And 5d is a digital signal processing-integrated circuits unit which performs calculation according to the control signal of the personal computer 2a by the maximum value and the minimum value. The digital de-signal processing-integrated circuit unit 50 is a digital signal processor (DSP)

Signal Processor), ROM (Read Only Memory), RAM (Random Access Memory) and the like.

Next, the overall operation of the present invention will be described with reference to FIGS. 2, 3, 4, and 5.

First, the personal computer 2a is loaded with software suitable for the inspection and adjustment of the circuit board under test, and the examiner assumes that the personal computer 2a is operated by the keyboard 2b.

First, the control signal of the personal computer 2a causes the programmable power supply 2f to supply a predetermined voltage and current to the circuit board 2r to be measured through the GPIB interface 2e. Causes the video signal generator 2g to generate a predetermined video signal via the GPIB interface 2e. The motor and the trigger signal generator 2h generate a trigger signal, a deck switch signal, a drum motor signal, and a capstan motor signal using the video signal according to the control signal of the personal computer 2a. The radio frequency signal generator 2i generates the same radio frequency signal as the signal generated when the video cassette tape is played back by applying the video signal, the drum motor signal and the capstan motor signal. The first selection circuit unit 2j selectively supplies the video signal, the deck switch signal, the drum motor signal capstan motor signal, and the radio frequency signals to the circuit board 2r under the control signal of the personal computer 2a.

In the case where the adjustment-inspection targets the digital data of the circuit board 2r to be measured, the trigger signal from the motor and the trigger signal generator 2h is input to the digital signal processor 21. The digital data of the circuit board 2r to be measured is input to the digital signal processing unit 21 via the second selection circuit section 2k. The digital signal processor 21 performs calculation on the digital data according to the trigger signal and the control signal of the personal computer 2a, and transmits the result to the personal computer 2a via the AT bus.

When the adjustment-checking targets an analog signal of the circuit board 2r to be measured, the second selection circuit section 2k is configured to generate various signals generated by the circuit board 2r to be measured according to the control signal of the personal computer 2a. Analog signals, i.e., signals applied among SI (1) ... SI (N) are selected and input to the signal amplifier 2m. The signal amplifier 2m amplifies or attenuates the selected signals to meet the input specifications of the analog signal processor 2n, and inputs the selected signals to the frequency measurement unit when frequency measurement is required. The analog signal processor 2n is an oscilloscope circuit board, which has a peak to peak voltage and an effective value of an input signal.

Root Mean Square voltage, phase difference, frequency, period, etc. are measured.

The analog signal processing section 2n and the frequency measuring section 2o transmit the measured data to the personal computer 2a via the AT bus.

The personal computer 2a receives the data of the digital signal processor 21, the analog signal processor 2n, and the frequency measuring unit 2o and compares the data with the stored reference data. The control signal required for the inspection item of the next step is outputted, otherwise, the motor drive part 2p is controlled to adjust the variable resistance on the circuit board 2r to be measured by the adjusting motor 2q. The adjustment is repeated until the measured data matches the reference data. On the other hand, data that does not match the reference data is output to the monitor 2c and the printer 20 to provide data for the failure analysis (failure analysis).

The present invention is not limited to the above embodiment. For example, a television for displaying an image in accordance with the output signal of the circuit board for the camcorder may be added and used if necessary.

As described above, according to the present invention, it is possible to provide an automatic inspection-adjustment system capable of not only applying a deck of a video cassette recorder but also inspecting-adjusting a digital signal.

Claims (5)

A processing unit which performs overall control with suitable software and hardware and shows the result; A video signal generator for generating a video signal according to a control command of the processing device; A motor and a trigger signal generator configured to generate a predetermined motor signal and a trigger signal using the video signal; A radio frequency signal generator for generating a radio frequency signal during play back using the video signal and the motor signal; A first selection circuit unit for selectively inputting the video signal, the motor signal, and the radio frequency signal to a circuit board for a camcorder; A second selection circuit section for selectively outputting various signals output from the circuit board for the camcorder to be inspected; A digital signal processing unit for processing the digital signal input from the second selection circuit unit to perform a necessary operation and transmitting the result to the processing apparatus; A signal amplifier for amplifying or attenuating the analog signal input from the second selection circuit unit; An analog signal processor for measuring characteristics of an analog signal input from the signal amplifier and transmitting the measured data to the processing device; An electric motor driving unit capable of driving the electric motor by a control command of the processing apparatus; And a motor for adjusting and adjusting a variable resistor on the circuit board for the camcorder by the motor driving unit. A system for automatically checking-adjusting a circuit board for a camcorder, characterized in that it comprises a. According to claim 1, wherein the motor and the trigger signal generating unit, a vertical synchronous signal separation circuit unit for generating a separate vertical synchronous signal included in the video signal output from the video signal generator control signal and the vertical synchronous signal of the processing device A programmable counter for generating drum motor signals, capstan motor signals, and trigger signals according to control of the controller; And a latch circuit for generating a deck switch signal in accordance with a control signal of the processing apparatus. 2. The apparatus of claim 1, wherein the second selection circuit unit comprises: an interface for generating signals of a specified specification according to a control signal of the processing apparatus; A buffer unit which receives digital signals or analog signals from the circuit board under test and outputs signals having a specified specification; And a relay unit for controlling analog signals from the circuit board under measurement in accordance with a control signal from the interface. A system for automatically checking-adjusting a circuit board for a camcorder, characterized in that it comprises a. The digital signal processor of claim 1, further comprising: an interface unit configured to generate signals having a specified specification according to a control signal of the processing apparatus; A maximum value circuit section for sequentially storing a maximum value of an input digital signal; A maximum value circuit section for sequentially storing a minimum value of an input digital signal; And digital signal processing-integrated circuits for performing arithmetic operations according to control signals of the processing apparatus using the maximum and minimum values. A system for automatically checking-adjusting a circuit board for a camcorder, characterized in that it comprises a. 5. The camcorder according to claim 4, wherein the digital signal processing-integrated circuit unit includes a digital signal processor (DSP), a read only h4 emory (ROM), and a random access memory (RAM). System.