From Bob Pease's web pages at National:
QUOTE
The origin of the WOM - the "Write Only Memory"
An engineer at Signetics, frustrated by the long and useless sequence of approvals for data sheets (during which no actual checking occurred), once made up a spec for a "Write Only Memory" (a "WOM") and sent it along with a batch of other data sheets to be approved. After all, if you are selling "Read Only Memories", why not have a "Write Only Memory"? It's perfectly logical - - which is why the managers saw nothing wrong with the data sheet.
The WOM data sheet went through the approval chain, just fine, and wound up in Signetics' new products catalog. This came to the attention of the managers at Signetics, only after customers began asking for price and delivery. Signetics shortly printed up new "corrected" databooks, without any WOMs, and asked for the "erroneous" ones to be returned. But customers soon got word of why they asked for returns, and hid them properly.
About 1974, Signetics bought a two-page, full-color spread in the April issue of ELECTRONICS Magazine, and published the WOM data sheet, as a (rather expensive) April Fool's Joke. This version of the WOM data sheet shows the various features of Signetics' Model 25120 "fully-encoded, 9046 x N Random Access, Write Only Memory". This advertisement has been saved, and greatly prized by engineers, for many years. We recently found a copy of this data sheet, in very good shape except for where it had been punched for a 3-ring binder. See the next pages.
This was not the end of the WOM. Signetics also brought out a promotional pamphlet, " Be Famous!! Have a WOM named after you." Unfortunately, not many of these survive. If anybody can loan us a good photocopy, we would love to add it to these pages.
At many companies, managers are accused of not having any sense of humor. But in this case, the Signetics guys did it right! Even if it did cost them a lot of money!! And our managers here at National approved my posting of this Data Sheet on my web site - to show that we have a good sense of humor, too!
Further, as we pointed out in a recent web-cast, XILINX makes FPGA's such as the XC4V LX15-10 SF363 - - which can be used in conjunction with our 3-Giga-samples-per-second ADC's, at such high data rates, that they are faster than most WOMs. The FPGA's can then give you back your data at a slower, controlled rate - - whereas WOMs never give you your bits back!