FLIP CHIP

FLIP CHIP was DEC's trade name for a lengthy series of small cards used to build computers, and devices for them. (It should not be confused with the generic technology term 'flip chip'; the DEC version, properly spelled with all capital letters, as in the trademark filing, got its name from the fact that some early FLIP CHIPs used flip chips.)

They were introduced as a cost-reduction measure; a FLIP CHIP plugged directly into a 144-pin connector block with wire-wrap pins on the back side; automatic Gardner-Denver wire-wrapping equipment could wire the connector blocks to produce larger functional modules.

Early FLIP CHIP modules were single-height, normal-length modules with contact fingers on one side of the PCB only (the so-called 'solder' side); the contact pads were 'numbered' from the DEC Alphabet.

The earliest FLIP CHIPs, introduced in 1964, used discrete transistors. FLIP CHIPs incorporating IC technology soon followed, and the limited number of contact pins eventually became a problem, so that eventually contact fingers were added on the other ('component') side as well.

The following FLIP CHIP families ('series', in DEC terminology) were introduced over the years:

• R-Series (red handles); intended to be easy to use, and used diode gates and diode-capacitor-diode circuits
• S-Series (also red handles); first developed for the original PDP-8; same basic technology as the R-Series, with component variations for greater speed
• B-Series (blue handles); first used on the PDP-7, and later in the famous KA10 PDP-10 CPU, they used silicon transistors
• A-Series (amber handles); analog cards
• G-Series (green handles); specialized modules that are part of a specific larger system
• W-Series (white handles); input/output to external circuitry
• K-Series (blacK handles); industrial control applications
• M-Series (magenta handles); carried the then-new TTL chips, first used in the PDP-8/I

DEC continued to use the name up into the period when [[extended-length quad-height cards started to appear, e.g. in the KA11 CPU. However, although these special-purpose cards are labelled 'FLIP CHIP's, they are generally not considered to be 'true' FLIP CHIPS; the name is generally only used to refer to the smaller, general-purpose cards.

External links

• In the Beginning and linked subsequent pages
• Digital Equipment Corporation PDP-7
• FlipChip Modules