Tutorial on Diode Arrays

Multiple diode packaging or diode arrays have been an important semiconductor product. They save assembly time and improve reliability over individually packaged diodes. In general, the term diode array implies four or more diodes in a single package. The most efficient packaging scheme is typically 8 diodes or more in a dual inline package, a DIP.

Other packages are the SIP, a single inline package, the flat pack, and even a surface mount diode array. Although multiple diode arrays can incorporate different type diodes, the most popular arrays incorporate a fast, small signal diode such as the 1N4148; and the core driver arrays which employ a fast switching, higher current, 100mA diode. Of course there are various diode configurations for, say 8 or more diodes. If two independent leads are brought out for each diode, a 16 leaded DIP would be fully utilized.

On the other hand, if a common cathode or common anode connection was used internally, a 16 pin DIP would accommodate 14 diodes. Other common connections are available, and even more esoteric connections are possible, limited only by cost and one’s imagination. Many manufacturers have discontinued supplying diode arrays. The most notable are Fairchild with their FSA identification types and Motorola and their MAD and MMAD prefixing.