Battery Connectors-JST Type
JST is a standard of electrical connection used widely across a spectrum of electrical applications. It’s defined as a Japanese Solderless Terminal and is manufactured by a company of the same name. The JST range includes a variety of families of connectors with varying pin to pin distances (known as pitches). The JST system was primarily designed to bridge an electrical connection or carry an electrical signal, and due to this, it is not advised to be using them for any mechanical process where the connector will be under any stresses or forces! We see them attached to batteries, motors, circuit boards and more; anything that is mounted still is fair game for this inexpensive and reliable connection type. The only issue with JST is the confusing naming scheme that often has hobbyists chasing their tails with connectors ending up .05mm too big or small for their needs. We’ve put together this primer on JST connectors so that you’ll understand the conventions associated with these connections.
Naming Rules
| JST | -XXX | -X |
| Japanese Solderless Terminal | Family | Dimensions |
The JST connector titles are confusing; many online vendors have no idea what the standard is based around and easily mess up the ten different families. Each family has a dozen sub-categories to its name too. We want to clear the air on this naming scheme, the JST part just refers to the solderless connection type, all of the connectors share the same type of connection. The following suffix (-XH, -SH, etc.) refers to the shape/style of the connector; these families share the Pin-to-Pin Pitch but not the shape and size of the housing. To define that size, the number/letter combination past the family specification will refer to the size of the unit. If you are looking for a particular replacement part for your project, it will be pertinent for you to know the full specification you’ll need. It’s worth noting that each family of connectors has its own current/voltage/wire size ratings. Beware of the imperial/metric conversions too, for example, a common issue is that 2.5mm connectors not being the same as 2.54mm (.1 inch) connectors despite their often misleading titles.
Wire-to-Board Connectors
| JST Series | Pin-to-Pin Pitch |
Pin Rows |
Current (Amp) |
Voltage (Volt) |
Wire Size (AWG) |
Shroud | Lock | Notes | Data sheet |
| VH | 3.96 mm (0.156 in) | 1 | 10 | 250 | 22 to 16 | Yes/No | Yes | Unshrouded seems to be more popular than shrouded. | JST VH |
| RE | 2.54 mm (0.100 in) | 1 | 2 | 250 | 30 to 24 | No | No | Similar to female “DuPont” connectors and male pin headers. RF series is double row. | JST RE |
| EH | 2.50 mm (0.098 in) | 1 | 3 | 250 | 32 to 22 | Yes | No | Not 0.1-inch pitch. | JST EH |
| XA | 2.50 mm (0.098 in) | 1 | 3 | 250 | 30 to 20 | Yes | Yes | Not 0.1-inch pitch. | JST XA |
| XH | 2.50 mm (0.098 in) | 1 | 3 | 250 | 30 to 22 | Yes | No | Not 0.1-inch pitch. Used by many radio control (R/C) batteries. | JST XH |
| PA | 2.00 mm (0.079 in) | 1 | 3 | 250 | 28 to 22 | Yes | Yes | Used by FMA Cellpro R/C battery chargers. | JST PA |
| PH | 2.00 mm (0.079 in) | 1 | 2 | 100 | 32 to 24 | Yes | No | Compatible with KR (IDC), KRD (IDC), CR (IDC) series. | JST PH |
| ZH | 1.50 mm (0.059 in) | 1 | 1 | 50 | 32 to 26 | Yes | No | Compatible with ZR (IDC) and ZM (crimp) series. | JST ZH |
| GH | 1.25 mm (0.049 in) | 1 | 1 | 50 | 30 to 26 | Yes | Yes | Not 0.05-inch pitch. Sometimes confused with Molex PicoBlade. | JST GH |
| SH | 1.00 mm (0.039 in) | 1 | 1 | 50 | 32 to 28 | Yes | No | Compatible with SR (IDC) and SZ (IDC) series. | JST SH |
Wire-to-Wire Connectors
| JST Series | Pin-to-Pin Pitch |
Pin Rows |
Current (Amp) |
Voltage (Volt) |
Wire Size (AWG) |
Features | Notes | Data sheet |
| RCY | 2.50 mm (0.098 in) | 1 | 3 | 250 | 28 to 22 | Locking | Used in radio control (R/C), also known as BEC or P connector. Commonly found on small models, toys, and small LiPo packs. | JST RCY |
| SM | 2.50 mm (0.098 in) | 1 | 3 | 250 | 28 to 22 | Locking, High force | Used in some RGB LED decorative light strips. | JST SM |
There are a few guidelines that are suggested by the manufacturers when working with JST connectors; these are put in place to ensure you aren’t breaking your connector or using it in an incorrect way:
When connecting between components and board, you’ll want to have a little extra cabling available so that you aren’t putting additional forces onto your connector or crimp; constant pulling on the crimped wires can cause loose connections.
JST also recommend that you only have a movement freedom of 15 degrees on each of the axes from the connector directly out along the cables, again this helps to ensure your connection will operate as expected
You should stick to using tin-plated, annealed copper stranded wire for crimping connections between JST connectors.
Refer to the connectors data sheet for information on the crimping tool you’ll need to use for the particular family.
JST Popular Connectors Type
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| JST EH-2 | JST EH-3 | JST SHR-02V-S-B | JST SHR-03V-S-B |
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| JST PH 2 | JST PH 3 | JST XH-2 | JST XH-3 |
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| JST SMR-02V-B | JST SMP-02V-BC | JST ZH | JST ELR-02V |
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| JST NVR-02 | JST VHR-2N |