SODIMM Connectors & DIMM / DDR Socket Selection

Module pin counts, lengths, pitches and supply voltages on this page follow the JEDEC DDR2 / DDR3 / DDR4 / DDR5 module standards; every KINGCONN socket value comes from the part drawings on this site.

DIMM vs SO-DIMM: the socket follows the module standard

DIMM 133.35 mm compared with SO-DIMM 67.6 mm (DDR2/DDR3) and 69.6 mm (DDR4/DDR5) drawn to scale — Module lengths per JEDEC, to scale. Desktop and server boards use DIMM; notebooks and embedded boards use SO-DIMM.

A memory socket is keyed to the module generation the board is designed for, so the initial filter is simply matching the standard. DIMM is the full-length module used on desktop and server boards; SO-DIMM (small outline) is the short module used on notebooks, industrial PCs, network appliances and embedded carrier boards. The key notch position moves with every generation, so a socket of the wrong generation physically rejects the module — which is the point.

Generation	DIMM pins	SO-DIMM pins	Supply	DIMM pitch	SO-DIMM pitch
DDR2	240	200	1.8 V	1.0 mm	0.6 mm
DDR3	240	204	1.5 V	1.0 mm	0.6 mm
DDR4	288	260	1.2 V	0.85 mm	0.50 mm
DDR5	288	262	1.1 V	0.85 mm	0.50 mm

Pin count and pitch are why a DDR4 SO-DIMM socket at 0.50mm pitch cannot be tooled from a DDR3 SO-DIMM socket at 0.6mm: the contacts, the housing length and the key rib are all different parts. The supply voltage matters for the socket too — contact plating and current rating are specified against the module's rail.

KINGCONN DIMM / DDR sockets

Part	Type	Positions	Pitch	Height
7DDR2-F0-0002	DDR2 SO-DIMM	200	0.6 mm	5.2 mm
7DDR4-F0-0007	DDR4 SO-DIMM	260	0.50 mm	5.2 mm
7DDR4-F0-0008	DDR4 SO-DIMM	260	0.50 mm	9.20 mm
7DDR5-F0-0001	DDR5 SO-DIMM	262	0.50 mm	4.0 mm

The KINGCONN DIMM (DDR) series covers DDR2 SO-DIMM at 200 positions and 0.6mm pitch, DDR4 SO-DIMM at 260 positions and 0.50mm pitch, and DDR5 SO-DIMM at 262 positions and 0.50mm pitch. Heights published across the family are 4.0mm, 5.2mm and 9.20mm.

What DDR5 asks of the socket

DDR5 moves the power-management IC onto the module, so the socket delivers a 5 V input rail rather than the final 1.1 V, and the current is spread over the contacts differently from DDR4. The module is also split into 2 independent 32-bit sub-channels with a re-ordered signal map, which is why the 262-pin DDR5 SO-DIMM notch is deliberately offset from the 260-pin DDR4 notch. KINGCONN 7DDR5-F0-0001 is a 262-position, 0.50mm-pitch, 4.0mm-high DDR5 SO-DIMM socket.

Height and orientation

In a fanless embedded chassis the socket height decides whether the module clears the heat spreader and the lid. The low 4.0mm and 5.2mm profiles hold the module close to the board; the 9.20mm profile lifts it for airflow or for a component under the module. Orientation (standard or reverse) sets which side the module tilts toward and therefore where the retaining clips sit — fix it together with the thermal and mechanical design, not after.

Materials and compliance

Housings are LCP rated UL94V-0; contacts are phosphor bronze. RoHS compliant, and every published value carries its source drawing number — verify against the original drawing before committing the layout.

Legacy boards

Embedded platforms outlive consumer memory generations by years. A DDR2 SO-DIMM socket is still a current KINGCONN part for that reason. If the socket your BOM specifies has gone end-of-life, send the part number or drawing to service@kingconn.com.tw and KINGCONN evaluates supply from existing tooling; see also the discontinued connector replacement guide.

KINGCONN DIMM sockets

7DDR2-F0-0002DDR2 200P STD H:5.2mm

7DDR4-F0-0007DDR4 SO DIMM 260PIN STD H:5.2mm

7DDR4-F0-0008DDR4 SO DIMM 260PIN STD H:9.2mm

7DDR5-F0-0001DDR5 STD 262P H:4.0mm

7DDR2-F0-0006DDR H:5.2 TYPE Reverse For 200 IN BLACK

DDR2, DDR4 and DDR5 SO-DIMM sockets at 5.2, 9.2 and 4.0mm heights.

FAQ

What is the difference between a DIMM socket and a SO-DIMM socket?

DIMM is the full-length desktop / server module (133.35 mm); SO-DIMM is the short module for notebooks and embedded boards (67.6 mm for DDR2 / DDR3, 69.6 mm for DDR4 / DDR5). Pin counts and notch positions differ, so the sockets are not interchangeable.

Can a DDR4 SO-DIMM socket take a DDR5 module?

No. DDR4 SO-DIMM has 260 pins and DDR5 has 262, the key notch sits in a different place, and the supply drops from 1.2 V to 1.1 V. The socket key blocks a module of the wrong generation.

What should an embedded board designer check when picking a DIMM socket?

Match the module generation and pin count, then check the socket height (KINGCONN publishes 4.0, 5.2 and 9.20 mm) against the heat spreader and enclosure, then the orientation (standard or reverse), which sets the side the module tilts toward.

What is the contact pitch of a DIMM socket?

Per JEDEC: DDR2 / DDR3 DIMM 1.0 mm, DDR4 / DDR5 DIMM 0.85 mm; SO-DIMM is 0.6 mm for DDR2 / DDR3 and 0.50 mm for DDR4 / DDR5. KINGCONN SO-DIMM sockets publish 0.6 mm and 0.50 mm accordingly.