Zig-zag in-line package

The zig-zag in-line package or ZIP was a short-lived packaging technology for integrated circuits, particularly dynamic RAM chips. It was intended as a replacement for dual in-line packaging (DIL or DIP). A ZIP is an integrated circuit encapsulated in a slab of plastic, measuring about 3 mm x 30 mm x 10 mm. The package's pins protrude in two rows from one of the long edges. The two rows are staggered by 1.27 mm (0.05"), giving them a zig-zag appearance, and allowing them to be spaced more closely than a rectangular grid would allow. The pins are inserted into holes in a printed circuit board, with the packages standing at right-angles to the board, allowing them to be placed closer together than DIPs of the same size. ZIPs have now been superseded by surface-mount[?] packages such as the thin small-outline packages (TSOPs[?]) used on single-in-line memory modules (SIMMs) and dual-in-line memory modules (DIMMs).