There are a variety of date coding schemes in use. Here are some of them. Often, it's possible to confuse which is the device code and which is the date code. Date codes are often in a different font, of a different size, or placed in a different orientation. Sometimes they are incorporated into the code number - where possible this will be indocated on the code entry by 'xx' and a note in the data entry. Some devices are only marked with the month of production.
Method 1
2 characters from tables below in form YM for year, month
|
Year
|
2002
|
2003
|
2004
|
2005
|
2006
|
2007
|
2008
|
|
Code
|
N
|
P
|
R
|
S
|
T
|
U
|
V
|
|
Month
|
Jan
|
Feb
|
Mar
|
Apr
|
May
|
Jun
|
Jul
|
Aug
|
Sep
|
Oct
|
Nov
|
Dec
|
|
Code
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
O
|
N
|
D
|
Another alternative year table...... likely to apply to General Semiconductor products up to 2000
|
Year
|
1994
|
1995
|
1996
|
1997
|
1998
|
1999
|
2000
|
|
Code
|
E
|
F
|
H
|
J
|
K
|
L
|
M
|
Method 2
2 characters from tables below in form YM for year, month
|
Year
|
1997
|
1998
|
1999
|
2000
|
2001
|
2002
|
2003
|
2004
|
2005
|
|
Code
|
7
|
8
|
9
|
0
|
1
|
2
|
3
|
4
|
5
|
|
Month
|
Jan
|
Feb
|
Mar
|
Apr
|
May
|
Jun
|
Jul
|
Aug
|
Sep
|
Oct
|
Nov
|
Dec
|
|
Code
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
A
|
B
|
C
|