Top Mark Search

Top mark refers to the device identification mark found on Fairchild Semiconductor packages. It is used for determining whether a product is genuine and matches your order.

(Please enter at least 4 characters of a product number)
Certain top marks refer to manufacturing date and assembly plant, and their values are dynamic
This search tool uses symbols, e.g. &Y, to stand for dynamic top marks
In search results, static marks are displayed in plain text, while dynamic marks are displayed in bold font with short descriptive text in parenthesis as link to help webpage

Top Mark Convention Symbol Legend

Symbol Format Description
$Y FS or Fairchild Semiconductor (FSC) logo graphic
&Z Z Designates the Assembly plant code
&4 XXYY 4-Digit Date code format
&3 XYY 3-Digit Date code format
&2 XY 2-Digit Date code format
&G YY Weekly Date code format
&T TT Die Run Traceability Code
&W ---- Six-Week Binary Datecoding Scheme
&V --- Eight-Week Binary Datecoding Scheme
&Y ---- Binary Calendar Year Coding Scheme
&C T Single digit Die Run Code (last digit of the two digit code)
&U U Wafer Fab Code
&E    Designates Space
&. . Pin one dot (For SC70, SOT23, MLP binary marking type and WLCSP)
&H Lot Number Last 3 digits of workstream lot number
&O Plant Code identifier on Tiny Logic Package
&K KK 2-Digit Lot Run Traceability Code

Top Mark Example

Line 1: &Y (Binary Year)

Line 2: &O (Plant Code) 1234&C (Die Run)

Line 3: &. (Pin One) &O (Plant Code) &E (Space) &V (Binary Week)

Top Mark Example

SMA/SMB/SMC Products

Line 1: $Y (Logo) &Z (Assembly Plant) &3 (Date Code)

Line 2: SMD

Top Mark Products