Which of the following statements regarding the handling and application of CMOS devices...
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Which of the following statements regarding the handling and application of CMOS devices is/are valid?
Show answer & explanation
CMOS devices are highly susceptible to Electrostatic Discharge (ESD) due to the thin gate oxide layer of the MOSFETs. All three listed precautions—preventing hot-plugging, ensuring common grounding of equipment, and using antistatic packaging—are industry-standard practices to prevent permanent device failure.
Step-by-step Derivation:
Step 1: Analyze Option A. Inserting a CMOS device into a powered circuit (hot-plugging) can cause transient current spikes or voltage mismatches between the device pins and the socket, potentially leading to latch-up or gate oxide breakdown. Thus, A is valid.
Step 2: Analyze Option B. To prevent the buildup of static electricity on the operator or the equipment, all conductive surfaces (workbenches, tools, and test gear) must be bonded to a common earth ground. This ensures that any accumulated charge is safely dissipated. Thus, B is valid.
Step 3: Analyze Option C. During transport and storage, CMOS devices can accumulate charge via friction (triboelectric charging). Antistatic tubes or conductive foam provide a Faraday-cage-like environment or a controlled dissipation path to prevent high-voltage discharges. Thus, C is valid.
Step 4: Since options A, B, and C are all standard and necessary precautions for handling CMOS devices, Option D ('All of these') is the correct choice.