CDM ESD 테스트 시스템

1. Basic Understanding of the Equipment

1.1 제품 개요

The ESD-CDM (Charged Device Model) CDM ESD Test System is a high-precision immunity test instrument specifically designed for “charged device contact discharge” scenarios involving semiconductor devices during production, transportation, and assembly. Its core function is to simulate the transient discharge process that occurs when a semiconductor device—which has become charged (e.g., through triboelectric charging or induced charging)—comes into contact with a grounded object. By precisely controlling parameters such as discharge voltage and current waveforms, it evaluates the device’s tolerance to this type of “latent electrostatic shocks,” enabling the early detection of risks such as internal circuit burnout and functional failure. It provides a testing basis for the reliability design, mass production quality inspection, and international compliance certification of semiconductor devices.

This system features an integrated “charge injection–contact discharge” design and is equipped with a high-precision charge measurement module, with a discharge voltage error of ≤±3%; It is compatible with fixtures for mainstream semiconductor packages such as DIP, SOP, QFP, and BGA. Equipped with a touchscreen display in both Chinese and English, it supports one-click configuration of test parameters, automated control of the discharge process, and real-time storage of test data, meeting the semiconductor industry’s requirements for high precision and high compatibility in testing.

1.2 적용 기준

This equipment fully complies with the following domestic and international CDM electrostatic discharge testing standards:

표준 번호	표준 제목
ANSI/ESDA/JEDEC JS-002-2014	Electrostatic Discharge (ESD) Sensitivity Testing—Charged-Device Model (CDM)—Component Level
IEC 60749-28 : 2022	Semiconductor Devices—Mechanical and Climatic Test Methods—Part 28: Electrostatic Discharge (ESD) Sensitivity Testing—Charged-Device Model (CDM)
AEC-Q100-011	Charged Device Model (CDM) Electrostatic Discharge Test
EIA/JESD22-C101	Test Method for Electrostatic Discharge Sensitivity Testing—Charged-Device Model (CDM)
ANSI/ESDS 5.3.1-2009	Electrostatic Discharge Sensitivity Testing – Charged Device Model (CDM) – Component Level
JEITA ED-4701/300 Test Method 305	Charged Device Model Electrostatic Discharge (CDM/ESD)
GB / T 4937.28-2024	Semiconductor Devices—Mechanical and Climatic Test Methods—Part 28: Electrostatic Discharge Sensitivity Testing—Charged Device Models (Equivalent to IEC 60749-28:2022)

1.3 Principles of the CDM Discharge Model

The Charged Device Model (CDM) simulates the physical process by which a semiconductor device accumulates static electric charge and then discharges it through contact between its pins and a grounded conductor. The device becomes charged through an induced high-voltage electric field, and when the device’s pins come into contact with a ground probe, the stored charge is rapidly discharged within nanoseconds, forming a discharge current pulse with a high peak and a fast rising edge. This pulse exerts a stress on the device’s internal gate oxide layer and metal interconnects, thereby evaluating the device’s electrostatic discharge (ESD) tolerance.

2. 안전상의 주의

2.1 근무 환경 요건

작동 온도: 15°C ~ 35°C; 작동 상대 습도: 30% ~ 60%. 고전압 아크 발생을 방지하기 위해 습도가 높거나 결로 현상이 발생하는 환경에서는 사용하지 마십시오.

주변 지역에는 강한 전자기 간섭, 진동원, 가연성 또는 폭발성 물질, 부식성 가스가 없어야 합니다.

Place it on a stable work surface; avoid tilting or inverting it, and keep it away from sources of vibration.

The distance between the equipment and walls or surrounding structures (such as other test equipment or shelving) must be at least 500 mm to facilitate 유지; 최소 1000mm of space must be left in front of the equipment to ensure smooth operation, with no obstructions in the surrounding area.

2.2 High-Voltage Safety Standards

2.2.1 보안 검색

전원 공급 장치가 장비와 호환되는지 확인하고, 전원 공급 장치가 제대로 접지되었는지 확인하며, 접지선에 손상이나 느슨함이 없는지 점검하십시오.

Grounding Requirements: The host unit’s protective grounding terminal (PGND) must be connected to ground; the grounding resistance must be ≤4Ω; the grounding cable must be securely connected, with no looseness or breaks.

2.2.2 운영 절차에 대한 안전 요구 사항

작업자는 전문 교육을 이수하고 본 설명서 및 관련 표준을 숙지해야 합니다. 비전문가는 장비를 작동하거나 분해할 수 없습니다. 본 장비에는 고전압 회로가 포함되어 있으므로 덮개를 열면 감전 위험이 있습니다. 수리가 필요한 경우 제조업체의 기술 담당자에게 문의하십시오.

Once the equipment is powered on, do not touch the test bench, high-voltage cables, discharge probes, or other related components to prevent electric shock;

Operators should ensure their hands are dry and free of metal jewelry; it is recommended that they wear insulated gloves while working;

감전 사고를 예방하기 위해 테스트 중에는 음식물을 섭취하지 마십시오.

여러 사람이 참여하는 경우, 역할과 책임을 명확하게 정의하고 오류를 방지하기 위해 테스트 시작 전에 서로 확인해야 합니다.

2.3 장비 안전 기준

고전압 케이블을 연결하거나 분리하기 전에 본체의 전원을 끄고 최소 5분 이상 기다려 내부 콘덴서가 완전히 방전되도록 해야 합니다.

고전압 플러그를 콘센트에 꽂을 때는 위치 고정 핀에 맞춰 꽂으십시오. 플러그가 제대로 맞춰지지 않았을 경우, 내부 구리 핀이 손상될 수 있으므로 절대로 억지로 꽂지 마십시오.

If you discover damage to high-voltage cables or loose connectors, stop using the product immediately and contact customer service to have them replaced;

Do not suddenly cut off the power or unplug or plug in the high-voltage connector while the equipment is running, to avoid damaging the high-voltage module;

딱딱한 물체로 터치스크린을 긁거나 날카로운 물체로 화면을 누르지 마십시오.

Avoid bumping the equipment during testing to prevent the device under test from shifting, which could cause the test to fail or damage the probes.

2.4 기타

본 설명서에 나와 있지 않은 사항에 대해서는 주의를 기울여 진행하시거나 당사에 문의해 주십시오.

3. 장비 개요 및 배선

3.1 정면도

그림 3-1를 참조하세요.

번호	주의 사항
정전기 방전 시뮬레이터
①	터치 스크린
②	High-Voltage Indicator Light
③	고전압 연결. 위치 고정 핀을 들어 올리고, 방전탑 고전압 플러그의 홈을 위치 고정 핀에 맞춘 다음, 천천히 끝까지 삽입합니다. 그런 다음 위치 고정 핀을 내려 고전압 플러그를 제자리에 고정합니다.
CDM Electrostatic Discharge Tower
④	Probe lift frame; the probe mounting location is directly opposite the test bench, as shown in Figure 3-2.
⑤	Standard test stand, adjustable for both position and height
⑥	BNC connector; use a coaxial cable to connect to an oscilloscope to view the output waveform. Note: Make sure the oscilloscope has a sufficient range, or use an attenuator to prevent damage to the oscilloscope.

3.2 배면도

그림 3-3를 참조하세요.

번호	주의 사항
정전기 방전 시뮬레이터
①	기기를 적절한 전원에 연결하기 위한 전원 코드 소켓(퓨즈 포함)
②	전원 스위치
③	PGND: Protective ground terminal; connect to earth using a ground wire.
④	Connecting the Signal Cables to the Discharge Tower
⑤	USB port: Can be used to connect a USB mouse to control the touchscreen, or to connect a USB flash drive to update the software.
⑥	LAN port, spare
CDM Electrostatic Discharge Tower
⑦	Grounding busbar: Connect the ground wire from the probe lifting frame to the grounding busbar, and then use a wire to connect the grounding busbar to the protective grounding terminal on the back of the Electrostatic Discharge Simulator.
⑧	High-Voltage Line Connection
⑨	Signal Line Connections
⑩	Connect the test bench ground wire to the protective ground terminal on the back of the Electrostatic Discharge Simulator.
⑪	High-Voltage Cable Connections on the Test Stand

3.3 Replacing the Discharge Tower

This Electrostatic Discharge Simulator can be connected to discharge towers used for various tests. If you need to replace the discharge tower for testing, please follow the operating procedures below strictly.

명령	주의 사항
①	Verify that the Electrostatic Discharge Simulator is in the “Test Stopped” state, then shut it down.
②	Disconnect all cables connecting the original discharge tower to the Electrostatic Discharge Simulator.
③	Connect all the cables between the new discharge tower and the Electrostatic Discharge Simulator.
④	Turn on the computer and run the new test.

4. Introduction to the Touchscreen Program

4.1 초기 화면

그림 4-1를 참조하세요.

번호	주의 사항
①	When the CDM discharge tower is connected to the host, “CDM Available” will be displayed; click it to enter the CDM test interface.
②	중국어와 영어 간 전환
③	제품 정보 페이지

4.2 CDM Test Interface

그림 4-2를 참조하세요.

번호	주의 사항
①	테스트 전압과 극성을 설정할 수 있습니다.
②	단일 테스트를 실행하려면 "단일 테스트"를 선택하십시오.
③	If you want to run continuous testing, select “Continuous Testing.”
④	You can set the number of tests; only consecutive tests are allowed.
⑤	시작/정지 테스트
⑥	Return to the Home Screen

5. CDM Electrostatic Discharge Testing

5.1 Preliminary Commissioning of the Test Bench Location

5.1.1 Placement Requirements for the Device Under Test

Operators should wear antistatic wristbands and antistatic clothing to prevent static electricity from the human body from damaging the devices under test; place the semiconductor devices under test with their pins facing upward in the center of the isolation plate,

5.1.2 Test Bench Commissioning

First, disconnect the high-voltage connection cables and place them on an insulated work surface. Then, refer to Section 4.2 to begin the test. Lower the probe at the standard speed. Based on the probe’s position as it descends, adjust the test stand’s height and horizontal alignment so that the probe makes just enough contact with the target pin upon reaching the bottom. Observe the contact status to avoid damaging the device pins due to excessive pressure. Once the adjustments are complete, stop the test and reconnect the high-voltage cable.

5.2 권장 표준 테스트 매개변수

In accordance with the ANSI/ESDA/JEDEC JS-002-2014 standard, the recommended parameters for routine testing are as follows: Discharge voltage: Select based on device class—Class 0 (<250 V), Class 1 (250 V to <500 V), Class 2 (500 V to <1000 V), Class 3 (≥1000 V); Discharge polarity: Test once for both positive and negative polarities; Number of discharges: At least 3 discharges per pin.

5.3 시작/정지 테스트

Set the test parameters as described in Sections 4.2 and 5.2, and start the test. If any abnormalities occur during the test, press the stop button to halt the test, make the necessary adjustments, and try again. After the test is complete, ensure that any internal residual charge is completely discharged, and remove the device under test. If the equipment will not be used again that day, you may turn it off.

5.4 테스트 결과 해석

모든 표준은 통일된 테스트 및 평가 논리를 따릅니다.

번호	주의 사항
Benchmarking	Before the CDM discharges, measure all parameters under the conditions specified in the standard and record the reference values.
방전 테스트	Perform CDM discharges at the specified voltage, polarity, and number of cycles as required by the standard
Comparison of Retest Results	After discharge, remeasure all parameters under conditions identical to those used for the baseline test.
Failure Determination	If any parameter exceeds the specifications, the device malfunctions, or there is physical damage, the device under test is deemed to have failed.
Level Confirmation	The highest voltage at which none of the samples failed shall be used as the final CDM withstand rating for the device under test.

6. Daily Maintenance and Care of Equipment

6.1 일일 청소 및 유지보수

After each test, use a clean, soft cloth to wipe dust from the main unit’s exterior, the touchscreen, and the surface of the discharge tower to keep the equipment clean; use a dedicated screen-cleaning cloth to clean the touchscreen. Do not use organic solvents such as acetone, and do not spray water directly onto the screen to clean it; Clean dust and foreign objects from the surfaces of the test bench, sensing plate, and isolation plate weekly to ensure good insulation performance; if the probe tip is soiled, gently wipe it with a lint-free cotton swab dipped in a small amount of anhydrous ethanol, and allow it to air dry before use.

The probe can be unplugged directly for cleaning or replacement; see Figure 6-1.

6.2 Items for Periodic Inspection

6.2.1 전기 연결 검사

Inspection Frequency: Once a month; Inspection Items: Check power cords, high-voltage cables, grounding wires, and communication cable connectors for looseness, oxidation, or damage; Remedial Actions: Tighten any loose connectors immediately; gently sand off any oxidation with fine-grit sandpaper; and replace any damaged cables immediately.

6.2.2 기계 구조 검사

Inspection Frequency: Once a month; Inspection Items: Check whether the test bench adjustment knobs turn smoothly, whether the probe bracket stop blocks are secure, and whether the probe extends and retracts normally; Remedial Actions: Apply a small amount of silicone grease to the adjustment mechanism for lubrication; replace the probe if it is deformed or worn.

6.3 장기 보관 요건

Before long-term storage, clean the entire surface of the unit and unplug all external cables; cover the unit with a dust cover and store it in a dry, well-ventilated environment free of corrosive gases; the storage environment should have a temperature of 0°C to 40°C and a relative humidity of ≤70%, and direct sunlight should be avoided; Every 3 months, power on the device and leave it in standby mode for 30 minutes to remove moisture and protect the high-voltage modules.

6.4 Calibration Interval Requirements

To ensure the measurement accuracy and operational reliability of the equipment, it is recommended that it be sent periodically to a qualified third-party metrology laboratory for calibration. The recommended calibration interval is 12 months. Users may determine the specific calibration interval based on frequency of use, environmental conditions, and quality system requirements.

7. 문제 해결 및 일반적인 문제 해결 방법

7.1 전력 관련 오류

결함 증상	가능한 원인들	순서
No display when powered on; power indicator light does not turn on	전원 코드가 제대로 꽂혀 있지 않습니다. 퓨즈가 끊어졌습니다.	Check the power cord connections; replace the fuse with one of the same rating after turning off the power.
터치스크린이 반응하지 않습니다	There are stains on the screen, and the system is malfunctioning.	Clean the screen surface; restart the device

7.2 고전압 고장

결함 증상	가능한 원인들	순서
High voltage cannot be applied after clicking “Start.”	High-voltage cables not properly connected, poor grounding, and dirt on the test bench surface	After turning off the power, unplug and replug the high-voltage cables, then tighten them; check and secure the ground wire; clean the surface of the test bench.

7.3 작동 오류

결함 증상	가능한 원인들	순서
Discharge cycles are not counted	The probe is not in contact with the device	Recalibrate the position to ensure good contact.
Communication error; the discharge tower is not operating	느슨한 통신 케이블	Tighten the signal cable connections after power is turned off

7.4 Waveform Anomalies

결함 증상	가능한 원인들	순서
The waveform peak is too low	Poor probe contact, voltage set too low	Clean the probe tip and adjust the contact pressure; verify and increase the set voltage.
The rising edge of the waveform does not meet specifications	Probe wear, excessive ground loop impedance	Replace the test probe; check the ground wire and reduce the ground resistance.
Many waveform artifacts	Electromagnetic Interference from the Surroundings	Eliminate sources of interference and use shielded cables