The
Ceramic Dual
In-line Package,
or CerDIP
is one of the most mature IC packages still in use
today. It is a rectangular ceramic package that has leads extending from both
of its longer sides, thus forming two sets of in-line pins.
|
 |
|
Figure 1. Example of a CerDIP |
The CerDIP is a hermetically sealed package
that keeps out moisture and contaminants once it is sealed. The CerDIP
package is composed of an upper part called the cap, and a lower part
called the base. The base has a cavity where the microchip is
mounted. The base is covered by the cap and then sealed with
molten seal glass. The seal glass provides a good hermetic seal
once it has cooled down and solidified, which is why hermetic packages
such as the CerDIP are used in military grade devices.
CerDIP lead counts range from 8 to 40.
CerDIP's typically come in two body widths: the narrow body which is
typically slightly less than 300 mils wide and the wide body which is
typically slightly less than 600 mils wide. The lead pitch of a
cerdip package is typically 100 mils.
Table 1. Properties of
Some Examples of CerDIP's
|
Lead
Count |
Width |
Length |
|
8
|
275
mils |
390
mils |
|
14
|
275
mils |
760
mils |
|
16
|
288
mils |
760
mils |
|
20
|
288
mils |
950
mils |
|
28
|
577
mils |
1450
mils |
|
40
|
577
mils |
2050
mils |
