JPS58206289A - Burst signal measuring device - Google Patents

Abstract

PURPOSE:To realize to decide instantaneously and correctly the quality of a burst signal, by constituting a device of a decision circuit which decides the quality by comparing voltage outputted from an integrating circuit with reference voltage value. CONSTITUTION:A burst signal 2 and chroma signals 3 inputted in a semiconductor device 1 to be measured are of sine waves of 3.579545MHz, etc., and a burst signal 4 and chroma signal 5 to be outputted are also of sine waves. A synchronization separating circuit 10 separates only the burst signal 4 out of the signals. A comparator 11 compares the burst signal 4 with a reference voltage value to take out difference voltage 14 as shown in the figure (b). If the difference voltage is larger than the ''good'' state of the burst signal, it means that a reference line exists upper than a limit line, and, if the difference voltage is smaller, it means that it exists lower than the limit line. When the difference voltage derived in the manner mentioned above is integrated, it becomes DC voltage 15 as shown in (c). Decision of the quality of the burst signal can be made by comparing the integrated voltage 15 with the reference voltage value.

Description

[Detailed description of the invention] The present invention relates to a burst signal measuring device.

Conventionally, determining whether a burst signal is good or bad has relied on visual observation using an oscilloscope. For this reason, it takes a lot of time to determine whether the product is good or bad.

FIG. 1 is a block diagram of an example of a conventional burst signal measuring device, and FIGS. 2(a) and 2(b) are signal waveform diagrams at various parts of the measuring device shown in FIG. 1.

A burst signal 2 and a chroma signal 3 are input to a semiconductor device under test 1, and a burst signal 4 and a chroma signal 5 are output.
was input into the oscilloscope 6, and out of the burst signal 4 and chroma signal 5 displayed on the measurer's oscilloscope 6, only the burst signal 4 was focused on and visually observed for determination.

3(at) to (C) are waveform diagrams for explaining the deviation between the burst signal 4 and the chroma signal 5 displayed on the oscilloscope of the measuring instrument shown in FIG. 1.

The criteria for the above-mentioned judgment are - For example, NT
Taking as an example a semiconductor IT device (hereinafter referred to as chroma video) having a circuit function for processing color signals and video signals of an SC-type Galebi receiver, the standard for the burst signal 4 shown in FIG. 3(a)K is The line 8 goes up and down beyond the limit lines 9 and 9', which are similar to the reference line 8 in Fig. 3(b): the reference line 8'' in Fig. 3(C1), and the line 8 in Fig. 3(b) is The reference line of burst signal 4 is within the limit line, so it is good.
(Cl determines that the burst signals are defective because the burst signals 4' and 4'' are outside the limit line.

1 Such measurements are also peak-to-peak (PEAKT).

PEAK') is generally used. When using a peak-to-peak measuring instrument, the burst signal is 4.4'.

4" can all be read as the same value.

As explained above, one conventional measuring device had the disadvantage that it required a lot of time to judge the burst signal because it had to be judged visually.

The present invention eliminates the above-mentioned drawbacks and provides a burst signal measuring device that makes it possible to instantly and accurately determine the quality of a burst signal.

The burst signal measuring device of the present invention includes a semiconductor to be measured,
a synchronization separation circuit that inputs the signals '-1' and '°'1 and separates only the burst signal from the burst signal and chroma signal output from the semiconductor device under test using a wateron periodic signal; a comparison circuit that compares the signal and a reference voltage value to extract a difference; an integration circuit that integrates the voltage output from the comparison circuit; and a comparison circuit that compares the voltage output from the integration circuit with the reference voltage value. and a determination circuit that determines whether it is acceptable or not.

Next, embodiments of the present invention will be described using the drawings.

FIG. 4 is a block diagram of one embodiment of the present invention.

In this embodiment, a burst signal 2 and a chroma signal 3 are input to the semiconductor device under test [1], and a burst signal 4 is output from the semiconductor device under test 1 from a burst signal 4 and a chroma signal 5.
Synchronous separation circuit 10 that separates only the water using a water periodic signal
, a comparison circuit 11 that compares the burst signal 4 and a reference voltage value and extracts the difference, an integration circuit 12 that integrates the voltage output from the comparison circuit 11, and a voltage output from the integration circuit 12 and the reference voltage. It is configured to include a self-sufficient circuit 13 that compares the value and determines pass or fail.

Next, the operation of the embodiment shown in FIG. 1 will be explained.

FIG. 5 is a waveform diagram at each part of the embodiment shown in FIG. 4.

The burst signal 2° chroma signal 3 input to the semiconductor device under test ill is a sine wave of 3.579545 MHz.

The burst signal 4 and chroma signal 5 outputted from the semiconductor device under test 1 are also the aforementioned sine waves. A synchronization separation circuit 10 separates only the burst signal 4 from these signals. Using the comparison circuit 11''Ir, the burst signal 4 is compared with the reference voltage value to extract the differential voltage 14 shown in FIG.
If this difference voltage is larger than the burst signal "good", the third
This means that the reference line shown in the figure is above the limit line, and if the differential voltage is small, it means that it is below. When the differential voltage obtained in this way is integrated, Fig. 5(c)
The DC voltage becomes 15 as shown in FIG. This integrated pressure 15
By comparing directly with gold standard pressure forming, it is easy to judge whether the noise signal is good or not.

As described in detail above, according to the present invention, it is possible to obtain a burst signal measuring device that can instantly and easily determine the burst signal, which has great effects.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an example of a conventional burst signal measuring device, Fig. 2 (a) and (b) are waveform diagrams of signals at each button of the measuring device shown in Fig. 1, and Fig. 31 (a) to (C) A waveform diagram for explaining the deviation between the burst signal and chroma signal displayed on the oscilloscope of the measuring instrument in Figure 1, Figure 4 is a block diagram of an embodiment of the present invention, and Figure 5 (a). ) ~ (C
) are waveform diagrams at various parts of the example of real power shown in FIG. 1...Semiconductor device under test, 2...Burst signal, 3...Chroma signal, 4...-...
Burst signal, 5...Chroma signal, 6...
... Oscilloscope, scope, 8 ... Base line (ground voltage), 9 ... Limit line, 10 ... Synchronization separation circuit, 11 ... Comparison Circuit, 12...
Integrating circuit, 13... Judgment circuit, 14...
-Differential voltage, 15...DC voltage. Agent Patent Attorney Susumu Uchihara (b) Mu-2 (α) (b) ((
:)(C)

Claims (1)

[Claims] A synchronous separation circuit inputs a burst signal and a chroma signal to a semiconductor device under test and separates only the burst signal from the burst signal and chroma signal output from the semiconductor device under test using a horizontal periodic signal; a comparison circuit that compares voltage values and extracts a difference; an integration circuit that integrates the voltage output from the comparison circuit; and a determination circuit that compares the voltage output from the integration circuit with a reference voltage value to determine pass/fail. A burst signal measuring instrument characterized by comprising: