|Monsanto MAN-3 & MAN-3A LED Displays (MAN3) ||
|Written by AnubisTTP on 2007-05-02
Devices included in this entry:
Monsanto MAN-3 (10-pin clear epoxy flat-pack; pictured in thumbnail)
Litronix MAN-3A (10-pin red epoxy quad inline package)
Monsanto MAN-3A (10-pin red epoxy quad inline package)
The MAN-3 is generally considered to be the first surface mount seven segment display ever made. This display is tiny: digit height is only 3mm and package dimensions are 6mm by 4mm. The unit has ten gold plated pins for mounting, and the two center pins are shared grounds. The earliest versions of this display are made using a single die which was encased in a water clear epoxy package. Later versions are encased in red plastic and have a significantly different internal construction, which makes use of a separate die for each LED segment. The single die version of this part has segments which are divided into 5 small light emitting sectors, which gives the display a distinctive quasi-bitmapped appearance when viewed with the naked eye. Strangely, the decimal point die does not appear to be a MV1 die, a departure from Monsanto's earlier LED products.
Monsanto MAN-3 LED Display, normal operation.
A MAN-3A LED display (left) shown with original Monsanto MAN-3.
Monsanto MAN3 LED displays, shown with packaging.
These rare pieces show MAN-3 displays under construction. Metal leadframes held the leads of each display in place until the epoxy had cured. Afterward, all but one pin would be cut from the frame, so the LED displays could be tested.
Monsanto MAN3 die, 20x magnification. Each segment contains 5 light emitting sectors.
The tiny size of the MAN3 forced clumsy workrounds when homebrew experimenters tried to incorporate the device into their builds. Here is a MAN3 that someone has shoehorned into a 10 pin TO5 adapter.
Commercially manufactured adapters were also available to make the MAN3 more palatable for electronics enthusiasts used to working with DIP packages.
Monsanto calculator display module with nine individual MAN-3A digits on a carrier PCB.
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