Shenzhen Shinzo Technology Co., Ltd. is now buying a new batch of IC chip testing equipment, testing equipment pictures as shown in this article, we not only want to do a good job of one-stop procurement services for customers, but also to give our customers to ensure that the chips are new and original. It is our aim to work together for the long-term development of each other's companies!
IC Chip, Integrated Circuit Chip, is to put a large number of microelectronic components (transistors, resistors, capacitors, etc.) formed integrated circuit on a plastic base, so as to make a chip.
At present, the quality of IC chip plays a very big role in the whole electronic products, which directly affects the quality of the whole product after market. So for the procurement personnel, how to correctly detect the quality of IC chip? This article briefly introduces several methods.
(TH2827C Precision LCR Meter)
1. Offline detection
This method is carried out when the IC is not welded into the circuit. In general, a multimeter can be used to measure the positive and reverse resistance values between the pins corresponding to the ground pins, and the IC in good condition will be compared.
(Digital storage Oscilloscope)
2. Online detection
(1) DC resistance detection, same as off-line detection
This is a multi-meter detection of IC pins in the circuit (IC in the circuit) DC resistance, AC and DC voltage to ground and the total working current detection method.
(2) Measurement of DC working voltage
This is a in the case of power, with a multi-meter DC voltage block DC supply voltage, peripheral components of the working voltage measurement; Test the DC voltage value of each IC pin to ground, and compared with the normal value, and then compress the fault range, out of the damaged components.
When measuring, pay attention to the following eight points:
①The multi-meter should have enough internal resistance, less than 10 times the resistance of the measured circuit, so as not to cause a large measurement error.
②Usually the potentiometer to the middle position, if it is a TV, the signal source to use standard color bar signal generator.
③watch pen or probe to take anti-skid measures. Because any instant short circuit is easy to damage IC. The following methods can be taken to prevent the sliding of the pen: take a bicycle with the valve core set on the table nib, and a long table nib about 05mm, which can make the table nib good contact with the test point, and can effectively prevent slipping, even if hit the adjacent point will not short circuit.
④When the voltage of a pin is not consistent with the normal value, it should be analyzed according to whether the pin voltage has an important influence on the normal operation of IC and the corresponding changes of other pin voltage, so as to judge the quality of IC.
⑤IC pin voltage will be affected by peripheral components. When the peripheral components occur leakage, short circuit, open circuit or variable value, or the peripheral circuit is connected to a variable resistance potentiometer, the position of the potentiometer sliding arm is different, will make the pin voltage changes.
⑥If the IC pin voltage is normal, IC is generally considered normal; If the IC part of the pin voltage is abnormal, it should start from the maximum deviation from normal value, check the peripheral components have no fault, if no fault, IC is likely to be damaged.
⑦For dynamic receiving devices, such as television, when there is no signal, the IC pin voltage is different. If it is found that the pin voltage should not change but change large, with the signal size and different positions of the adjustable element change but do not change, IC damage can be determined.
⑧For a variety of working mode of devices, such as video recorders, in different working modes, IC pin voltage is also different.
(DC Power Supply)
3. Ac working voltage test method
The AC voltage approximation of IC is measured by a multimeter with dB file. If there is no dB file, it can be inserted into a mouth in front of the pen. 1-0.5 "isolation of DC capacity. This pattern applies to those with lower operating frequencies. But be aware that these signals will be subject to natural frequencies and will vary from waveform to waveform. So the measured data is approximate value, for reference only.
(Function/Arbitrary Waveform Generator)
4. Total current measurement method
By measuring the total current of IC power supply, we can judge the quality of IC. Due to the majority of IC internal DC coupling, IC damage (such as PN junction breakdown or open circuit) will cause after the inverted port and cut-off, so that the total current changes. So measuring the total current can judge the quality of IC. The current value can be calculated by measuring the voltage on the resistance of the loop.
(Input)
Post time: Mar-17-2023