A DIP-64 package is a 64-lead dual in-line component with pins on a 2.54 mm (0.1 in) pitch, built as either plastic (PDIP) or ceramic (CDIP). It’s the largest common DIP pin count, and it ships in three different row-spacing standards — 15.24 mm, 22.86 mm, and 25.4 mm — so the dimension you need depends on which variant your part actually uses.

Key takeaways

• DIP-64 uses a fixed 2.54 mm lead pitch, but row spacing varies by manufacturer: 600 mil, 900 mil, or 1000 mil are all in active use.
• A shrink variant, SDIP-64, exists at 1.778 mm (0.070 in) pitch and 750 mil row spacing for a smaller footprint.
• Pin 1 sits at the top-left next to a notch or dot; numbering runs counter-clockwise.
• Classic 64-pin parts like the Motorola MC68000 shipped in the 600 mil row-spacing ceramic version — check the datasheet before you order a socket.
• Overall package length scales directly with pin count: roughly 56 mm long for the common 900 mil variant.

What a DIP-64 package is

DIP-64 is a through-hole IC package with two parallel rows of 32 pins each, for a total of 64 leads. It belongs to the dual in-line package family that JEDEC standardized starting in the 1960s, and it sat at the high end of practical DIP pin counts before designers switched to PGA for through-hole or QFP and BGA packages for surface mount at higher pin counts. Historically it housed early microprocessors — Motorola’s MC68000 used a 64-pin ceramic DIP package in early personal computers and workstations, and reference material shows a 1979 68000 housed specifically in the 600 mil row-spacing (DIP-600-64) body.

DIP-64 dimensions: three row-spacing variants

This is the detail most reference pages skip: “DIP-64” isn’t one fixed footprint. The lead pitch is fixed at 2.54 mm, but the distance between the two pin rows differs by manufacturer and by how old the part is. The KiCad footprint library ships DIP-64 variants at 15.24 mm (600 mil), 22.86 mm (900 mil), and 25.4 mm (1000 mil) row spacing, plus SMD-mount versions of the 600 mil and 650 mil spacing.

Row spacing	Lead pitch	Typical use	Notes
15.24 mm (600 mil)	2.54 mm	Older ceramic 64-pin parts (e.g., 68000-family CPUs)	Narrowest DIP-64; matches JEDEC’s 600 mil DIP family lineage
22.86 mm (900 mil)	2.54 mm	Common plastic and ceramic DIP-64	Most frequently stocked socket width for DIP-64
25.4 mm (1000 mil)	2.54 mm	Wide-body DIP-64 variants	Least common; verify against the specific datasheet

A rough overall size for the common variant: a DIP-64 package is roughly 56 mm long and 23 mm wide — consistent with the 900 mil (22.86 mm) row-spacing family once you add the lead overhang.

Design rule: never assume row spacing from the pin count alone. Pull the exact package drawing from the datasheet — the difference between 600 mil and 900 mil sockets is 7.62 mm, enough to make a socket physically not fit.

Pin numbering and orientation

Pin 1 location is marked by a notch, dot, or both on one end of the package, and pin numbering runs counter-clockwise from the top-left when the notch faces up. For DIP-64 that means pins 1–32 run down the left column and pins 33–64 run back up the right column, ending at pin 64 directly across from pin 1.

Land pattern / footprint calculation

For a rectangular DIP land pattern, the general land-area formula is A = (n/2 × 2.54) × (width + 1.65 mm), where n is pin count and width is the row spacing in millimeters.

Worked example for a 900 mil (22.86 mm) DIP-64: n = 64, so n/2 = 32. Pad column length = 32 × 2.54 mm = 81.28 mm.

That number is too long for a real board — the formula estimates land area, not usable footprint length; in practice, the pad rows for DIP-64 span roughly 78–79 mm center-to-center on 2.54 mm pitch (31 gaps × 2.54 mm = 78.74 mm), with 22.86 mm between rows. Use this to sanity-check a footprint before you commit to layout, but always verify against the manufacturer’s mechanical drawing rather than deriving it from the formula alone — package tolerances (lead width, standoff, corner radius) aren’t captured by the simplified equation.

Shrink DIP-64: the compact alternative

Microchip’s packaging spec lists a 64-Lead Shrink Plastic Dual In-line at 750 mil (19.05 mm) body width, and Zilog documents a 64-Lead Shrink Dual In-Line Package in its own mechanical data as a separate drawing from the standard DIP-64. SDIP-64 uses the shrink pitch of 1.778 mm (0.070 in) instead of the standard 0.1 in, packing 64 leads into a narrower body — useful when board space is tighter but through-hole assembly is still required.

When DIP-64 makes sense vs. surface mount

DIP-64 is a legacy and prototyping choice today, not a production-volume one. Every DIP pin needs a drilled and plated hole, which adds manufacturing cost and time compared to surface-mount assembly, and through-hole insertion and wave soldering are slower than pick-and-place and reflow. Long DIP leads also act as inductors, causing signal integrity problems above a few hundred MHz, so DIP-64 is unsuitable for any high-speed digital or RF signal path. It remains the right call for socketed prototyping, hand-assembly, education, and repair of legacy equipment where the original part shipped in DIP-64.

If your design needs 64 pins in production volume, the modern equivalents are a 64-lead QFP or a comparable BGA — Zilog’s own package set moves 64-pin devices to a 10×10×1.4 mm or 14×14×1.4 mm low-profile QFP alongside its legacy DIP-64 drawing.

Socket selection

Match the socket to the row spacing you confirmed above, not just the pin count. A 64-pin ZIF or standard DIP socket rated for 900 mil will not seat a 600 mil or 1000 mil part. 64-pin DIP sockets are commonly listed by lead spacing (e.g., 0.070 in for shrink-pitch parts) — order by both pin count and pitch/row-spacing together, never pin count alone.

FAQ

How big is a DIP-64 package?

It depends on the row-spacing variant, but the common 900 mil version runs roughly 56 mm long by 23 mm wide, with a fixed 2.54 mm lead pitch. Always confirm against the specific part’s datasheet.

What is the pin spacing on a DIP-64?

Standard DIP-64 uses 2.54 mm (0.1 in) pitch between adjacent pins in the same row. A shrink variant, SDIP-64, uses 1.778 mm (0.070 in) instead.

How do you find pin 1 on a DIP-64?

Look for a notch or dot at one end of the package body. With the notch facing up, pin 1 is the top-left pin, and numbering runs counter-clockwise around the package.

Is DIP-64 still used in new designs?

Rarely for production volume, since through-hole assembly costs more and DIP packages aren’t suited to high-speed signals. It remains common for prototyping, education, and repair of legacy equipment.

What replaces DIP-64 in surface-mount designs?

A 64-lead QFP is the direct pin-count equivalent for surface mount, with BGA options for higher-density boards.

Decision

Before you draw a DIP-64 footprint or order a socket, pull the exact mechanical drawing from the part’s datasheet and confirm which row spacing it uses — 600, 900, or 1000 mil, or the 750 mil shrink variant. If you’re specifying a new design rather than replacing a legacy part, default to a 64-lead QFP instead; reserve DIP-64 for socketed prototyping or repair work where the original part is genuinely DIP.