Introduction

“JST Connector” is either shorthand for a connector manufacturer called Japan Solderless Terminal, or a vernacular term for a range of different type of wire to board connectors, which either are, or resemble designs from Japan Solderless Terminal.

In the vernacular sense, precisely which type of connector is being referred to depends on who is using the term and in what context. On this page I’ll cover the most popular connectors from Japan Solderless Terminal. Many of which are referred to as “JST Connectors” in various circles.

Note that compatible connectors are made by other manufacturers. Where I specify part numbers, I’m only doing so for genuine parts. Most are stocked by Digi-Key (US) and Farnell (UK). Most will find it more convenient to source from eBay, however note that this is an unlikely source of genuine parts.

Content

• ZH (1.5mm pitch)
• PH (2.0mm pitch)
• XH (2.5mm pitch)
• XA (2.5mm pitch)
• EH (2.5mm pitch)
• SM (2.5mm pitch)
• RCY (2.5mm pitch)
• SH(1.0mm pitch)
• SHD (1.0mm pitch)
• GH (1.25mm pitch)
• VH (3.96mm pitch)
• Other types

Crimp tools

Official

JST offer high quality hand crimp tools for their popular connector families. These are mostly made by the German contract crimp tool manufacturer Wezag GmbH, will crimp the associated contacts perfectly and to specification, but are all expensive. I have listed the part numbers for these where available.

Some of these (particularly for PH/XH) are frequently seen on eBay second hand, and may be worth watching out for if you crimp a lot of these connectors, as they are an order of magnitude easier to use than even the best generic tools.

For more obscure types, no hand tool is offered, however JST do sell a hand frame (YRS-XXX) for mounting dies for their MKS-L applicator (used in the AP-K2N crimping machine), a very expensive solution, and the only option for production/mission critical applications.

Unofficial / Generic

Unlike many other connector families where there isn’t much in the way of good generic/budget crimp tools, there are many generic crimp tools specifically designed for JST contacts. Pictured above a two of the best available.

• Engineer PAD-11. Some may be familiar with the PA-09 – an expensive, crappy tool also designed for mainly JST contacts. The PAD-11 costs quite a bit more than the PA-09 but is significantly better made, contacts won’t get stuck in it after crimping, and it handles the smallest GH/SH types.
• IWISS IWS-2820M. A copy of the Engineer PAD-11. Not as well made but for the significantly lower price, it could be forgiven.
• Hozan P-707 will crimp larger JST contact types (2.5mm pitch and larger) better than the above two tools due to superior conductor crimping force.

ZH (1.5mm pitch)

ZH is one of the smallest pitch types of through-hole JST connector. Types smaller than this are all SMD. I am told these are common 3D printer related applications.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

PH (2.0mm pitch)

This 2.0mm pitch connector is very commonly seen in low cost consumer electronics as well as a plenitude of pre-fabricated hobbyist PCBs and parts. They’re dirt cheap, reasonably compact but not particularly robust.

A similar dual row type is also available (PHD) however using different contacts.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

The official tool is WC-240.

The WC-240 is nice to use, but there’s not a lot to set it apart from generic tools for occasional use. I personally crimp a large amount of PH, hence the investment in the official tool.

Left: Contacts crimped with PA-09. Right: Contact crimped with Original tool (WC-240).

XH (2.5mm pitch)

This is a slightly larger edition of the PH connector, except with 2.5mm pitch, and slightly larger contacts of a completely different design. Once again, mostly found in low cost consumer electronics. This family features a peculiar single position header and receptacle – a feature I always like to see in a connector family.

I don’t use these very much but one advantage of them is height. The mated assembly is considerably slimmer than any other type of connector I use. It’s a shame the pitch isn’t 2.54mm – I would use them a lot more otherwise. That said, you can usually jam 2 or 3 (maybe even 4) position headers onto strip board if needed.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

The official tool is WC-110

I wasn’t going to bother covering the differences between this tool and generic tools, because they looked so similar, but lately I’ve been noticing something –

When we look at the crimps top down from the rear, we see that the original tool has beautifully curled the insulation crimp ends around, pressing neatly on the insulation without piercing it. This explains one of my biggest gripes with these connectors, which went away when I started using the original tool: The insulation keeps tearing off.

This problem is particularly acute with this type of connector because the transition from wire to contact is at flush with the top of the housing, so if there’s already a tear created by the crimping process – it only takes a few movements back and forward to create the above mess.

XA (2.5mm pitch)

These are very similar to PH/XH however less common. Generally found in consumer products (for example: Japanese brand LCD televisions) which need to perform well in HALT testing.

They feature a positive latch instead of the weaker friction latch used by their PH/XH cousins. One rather unexpected feature is that they do not accept the same contacts as PH/XH. PA shares contacts with the PHD family. XA has its own unique type of contact which looks like a scaled-up PH contact.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

EH (2.5mm pitch)

EH is a 2.5mm pitch connector deployed in low cost products where a current carrying connector is needed, but PCB real-estate is highly constrained. They are significantly slimmer than XH connectors.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

SM (2.5mm pitch)

SM is an exclusively wire-to-wire type connector which has become extremely popular in recent times. Given that it has no wire-to-board option, I am unsure as to exactly why.

Example part numbers

RCY (2.5mm pitch)

RCY is a small 2 position only connector, and like SM is exclusively wire-to-wire. I’ve never seen or used one. It appears they’re commonly used for small battery packs.

Part numbers

It appears that a purposed designed hand crimp tool is only offered for male contacts. For female contacts the $1000+ YRS frame, supplied with the appropriate applicator dies is specified. Given that the conductor and insulation crimp is the same for each, the WC-121 would very likely crimp female contacts, but the locator would have to be folded down, and the contact positioned by hand.

SH (1.0mm pitch)

A teeny weeny surface mount only connector family from JST. Commonly found inside laptops for connecting various items to the motherboard. Housings are available with “wings” to aid disconnection. Housings are “SH” and headers are “SR”.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

SHD (1.0mm pitch)

Very similar to the above series, however in a dual row configuration. Commonly used in LCD / LVDS applications.

GH (1.25mm pitch)

Like the above series, also surface mount only however featuring positive latching mechanism and a completely different type of mating surface.

VH (3.96mm pitch)

VH is a larger type of JST connector featuring positive latching and is generally used in high voltage and/or high current connections. Power supply connections in Japanese brand appliances is the most likely place to find them.

Those visiting my site a number of years ago may have seen these pictured, but incorrectly identified as Molex KK .396 connectors. They do look similar, and have the same pitch spacing, but even I didn’t know my stuff once upon a time.

Example part numbers

Numbers in bold can be changed to order connectors with a different number of positions.

Other types

Just because it isn’t listed here, that doesn’t mean it’s not a JST connector. JST have a huge product range. Why make just one type of 2.5mm pitch wire-to-board connector when you can make 20? They’re all listed here.