How to Record Isolation Scope in Surplus Gate-Driver Inventory

1. Identify the Driver IC or Supplied Assembly

Establish whether the seller is offering a loose gate-driver IC, a driver board or a complete power assembly. Keep the manufacturer's device code separate from an assembly identifier. A board described as isolated may include several products with different roles, so its short description should not replace the identity of the actual sale item.

Retain the original marking, pack reference and available purchase or equipment record for that item. A partial family code should stay partial until supporting records identify the variant. Where a board's component list conflicts with visible identifiers, preserve the discrepancy instead of extending one documented device's features to every assembly in the group.

List any separately identified supply converter, isolator or other included hardware as part of the assembly record. Their descriptions do not automatically describe the gate-driver signal path. The important identification step is connecting each available document to the product it covers, rather than allowing one isolation annotation to stand for the whole board.

2. Name the Documented Isolation Path

TI's UCC21520 description identifies an isolation barrier between the input side and the two output drivers. It separately describes internal functional isolation between the two secondary-side drivers. These statements have different endpoints. Preserve those endpoint descriptions instead of combining them into an unqualified isolated field for every path in the product.

For an identified device, record the exact document and the path each supported statement addresses. An input-to-output entry and an output-to-output entry should remain distinguishable. If only one path is documented in the available evidence, leave the other unresolved rather than assuming the statement has the same scope for both paths.

Keep an assembly's supply description alongside, rather than inside, the device's signal-path record. A label describing an isolated supply does not identify which gate-driver path its component documentation supports. Resolve the signal question from the exact driver reference; do not infer it from the presence or appearance of a separate power component.

This distinction concerns documented product architecture, not instructions for connecting a circuit. It supplies no physical pin mapping, board wiring or operating arrangement. If an assembly-level path is uncertain, request its appropriate identification evidence instead of reconstructing a connection from a photograph or treating the named TI example as that assembly's design.

3. Separate Product Ratings from the Lot's Evidence

Retain a product's documented isolation description separately from observations about the physical lot. The manufacturer statement describes the identified product within its specification context. It does not demonstrate that a removed, repacked or unidentified unit presently retains that behaviour, and it should not be relabelled as an inspection of the offered stock.

Where condition history is known, identify the covered item and relevant installation or removal context. Keep visible package, board or terminal issues as observations with their evidence references. An intact housing or familiar board layout does not establish the condition of an internal barrier; missing history should remain explicit rather than being resolved by appearance.

If an existing report is available, preserve its identifiers, date, method and actual coverage. Distinguish the documented path it addresses from other possible paths or components in the assembly. A report for a board, another device or a small sample should not become an unexplained verification statement covering every loose driver in the offer.

Keep certificate references separate from product descriptions and lot reports. This guide does not review certificate coverage or translate a manufacturer's planned certification wording into a present approval. It gives no voltage or CMTI figures and no insulation-test procedure. Unread or unavailable evidence stays a specific documentation gap for further qualified review.

4. Request Review Without Insulation or Application Promises

Build the enquiry around the actual supply item and its supported isolation-path descriptions. Keep loose devices separate from boards and preserve variant or component-list uncertainties. The recipient should be able to see which statements concern the driver IC, which concern another assembly component and which have not been connected to the offered material. Confirm that the owner has authorised release of the described groups.

Ask for assessment of the supported groups and identify the unresolved path or variant question. Do not convert an isolated catalogue label into a promise that the material is suitable for a new high-voltage application. The customer's assembly and its engineering approval require their own evidence beyond a surplus inventory description.

For an ICULTRA gate-driver enquiry, provide complete available codes, the supplied-item list, applicable path references and existing condition records. State which reports or documents are missing. Any further verification, accepted lines and commercial terms need explicit confirmation for the offered scope; this identity record does not establish barrier health or a completed purchase.

Sources and further reading

• TI UCC21520 Product Description

TI's UCC21520 product description distinguishes the input-to-output isolation barrier from functional isolation between its secondary-side drivers. This guide uses that qualitative distinction without voltage, CMTI, certification or insulation-test conclusions.