JST Connector Family
Posted by SZFRS Engineering Team
JST is the most common connector brand in consumer and small-electronics cable assembly. The catalog runs into hundreds of series, but four families — PH, XH, SH, and EH — handle 80% of typical applications. Each has a specific pitch, current rating, and lock style that suits a particular set of use cases. Picking the wrong family means either oversizing (paying for current capacity you don’t need) or undersizing (running thermal margin too thin). This guide walks through what each family does well and how to choose.
Table of Contents
TL;DR — Quick Answer
PH (2.0mm pitch) is the consumer electronics workhorse — 2A per circuit, friction-fit, available 2-16 pin. The default for most PCB-to-wire connections in laptops, displays, signage, drones, IoT devices. XH (2.5mm pitch) handles slightly more current at 3A and uses a friction-lock latch — common in slightly larger PCB applications. SH (1.0mm pitch) is the compact specialist — 1A per circuit, fine pitch for space-constrained boards (smartphones, AR/VR, cameras, wearables). EH (2.5mm pitch) is the small lithium battery balance lead standard — used on every drone battery, RC LiPo, and small lithium pack. Below covers each family in practical detail with selection guidance.
PH Series — The Default Choice
The PH series is the most versatile family in the JST lineup. 2.0mm pitch, 2A per circuit, available in 2 through 16 positions, friction-fit (no positive lock). The PHR housing engages a B series PCB header to make the connection, and the JWPF and similar accessory parts allow various wire-management configurations.
Where PH dominates: laptop internal wiring (cooling fans, displays, peripherals), monitor and TV internal harnesses, digital signage controller boards, AR/VR headset internals, drone PCB-to-PCB and PCB-to-cable, IoT device internal wiring, POS terminal internal connections, and most consumer electronics where PCB-to-wire connections need to be reliable but not aerospace-grade. Our JST connector harness page covers the assembly capabilities in more detail.
The friction-fit retention is good enough for most applications but not great. PH connectors can vibrate loose under sustained vibration or rough handling. For applications where positive lock matters, XH or another series with latch is better. For space-constrained applications where 2.0mm pitch is too coarse, GH or SH series win.
XH Series — When Lock Matters
The XH series is similar to PH but stepped up — 2.5mm pitch, 3A per circuit, with a positive friction-lock latch on the housing. The latch engages a tab on the header, requiring deliberate pressing to release. This makes XH the standard for applications where vibration loosening or accidental disconnection is a real concern.
Where XH wins: small power supply harnesses where 3A current is common, 5V and 12V power distribution in larger consumer devices, charging connections in some battery-powered devices, slightly larger PCB-to-wire connections (printer mechanisms, slightly larger appliances), and any application where the connection might see vibration or shock. The 2.5mm pitch makes XH a bit larger than PH but the latching mechanism makes it more secure.
XH is also common in development kits and prototyping because the larger pitch is easier to work with by hand, and the positive lock prevents pulling out by accident during testing. We often recommend XH over PH for first-generation prototypes that will see manual handling, then assess whether to step down to PH for production volume to save space and cost.
SH Series — The Compact Specialist
SH series is the fine-pitch specialist — 1.0mm pitch, 1A per circuit, designed for space-constrained applications. Available 2-15 positions. The smaller pitch makes SH harder to work with manually but allows much higher contact density on the PCB.
Where SH dominates: smartphone internal connections (less common with the move to FPC, but still present), AR/VR headset internal high-density wiring, action camera internal connections (GoPro, DJI Action), wearable medical devices (CGM patches, ECG patches at the controller-side connector), small drones where space is at premium, hearing aids and small audio devices. Anywhere the device is fundamentally compact and millimeters of board space matter.
The current rating limits SH applications. 1A per circuit is fine for signal and low-power connections but inadequate for power distribution. For compact applications that need higher current, GH (1.25mm pitch, 1A) or ZH (1.5mm pitch, 1A) provide alternatives at slightly different size points.
EH Series — The Battery Balance Standard
The EH series has a specific dominant application — small lithium battery balance connectors. Every consumer LiPo battery for RC, drones, and small electronics ships with an EH balance lead matching the cell count (3-cell uses 4-pin EH, 4-cell uses 5-pin EH, 6-cell uses 7-pin EH). The standardization is nearly universal in the consumer LiPo ecosystem; chargers across the major brands (iCharger, ToolkitRC, ISDT) all accept EH balance leads.
EH is 2.5mm pitch, 3A per circuit. The balance lead application uses much lower current than the 3A rating (balance currents typically run 100-500 mA), so EH is over-rated for the balance task. The pitch and pin spacing match the LiPo industry’s standardization more than electrical optimization.
Where EH wins: drone batteries, RC vehicle batteries, FPV freestyle batteries, small power tool batteries, e-bike auxiliary battery monitoring, hobby and educational lithium pack programs. Anywhere the lithium pack ecosystem expects EH balance leads, that’s the family to use. Power tool packs (Milwaukee M18, DeWalt 18V/20V, Makita LXT) use proprietary connectors rather than EH for the main pack-to-tool connection, but internal balance and BMS sampling within the pack often still use EH-family connectors.
Side-by-Side Comparison Table
| Series | Pitch | Current Rating | Lock Style | Pin Range | Primary Application |
|---|---|---|---|---|---|
| PH | 2.0 mm | 2A | Friction-fit | 2-16 | General PCB-to-wire |
| XH | 2.5 mm | 3A | Friction-lock latch | 2-20 | Power, vibration-prone |
| SH | 1.0 mm | 1A | Friction-fit | 2-15 | Compact, mobile |
| EH | 2.5 mm | 3A | Friction-fit | 2-15 | Lithium battery balance |
| GH | 1.25 mm | 1A | Friction-lock latch | 2-15 | Compact with locking |
| ZH | 1.5 mm | 1A | Friction-fit | 2-15 | Compact, slightly larger than SH |
| NH | 2.5 mm | 10A | Friction-lock latch | 2-12 | Higher-current power |
| VH | 3.96 mm | 10A | Friction-lock latch | 2-12 | Larger appliances |
Application Selection Framework
| Application | Recommended JST Series | Reasoning |
|---|---|---|
| Laptop internal fan/peripheral | PH | Standard PCB-to-wire, 2A adequate |
| Monitor/TV internal | PH or XH | PH for signal, XH if vibration concern |
| Digital signage controller | PH | Standard signage internal wiring |
| AR/VR headset internal | SH or GH | Compact form factor |
| Drone main board to ESC | XH | 3A current, vibration-prone |
| Drone LiPo battery balance | EH | Industry standard for balance |
| Drone camera/gimbal cable | SH or GH | Compact, signal-level |
| Action camera internal | SH | Very compact form factor |
| POS terminal internal | PH | Standard commercial internal |
| POS receipt printer | XH | Power harness, vibration |
| IoT sensor PCB | PH or SH | Depends on form factor |
| Wearable medical patch | SH | Compact patient-side |
| Power tool internal BMS | EH | Battery balance/sampling |
| E-bike auxiliary harness | NH or VH | Higher current |
| Beauty equipment handpiece | PH or XH | Internal cable management |
| Industrial robot teach pendant | XH | Vibration, manual handling |
JST Alternatives — When to Look Elsewhere
JST isn’t always the right answer. Some applications fit better with other connector ecosystems:
- Higher-current applications: Beyond 3-10A, Molex MicroFit 3.0 (5A), Molex MiniFit Jr (9A), and Molex MegaFit (23A) are often better choices. Molex connector harness applications cover this range well.
- Sealed applications: JST families are not waterproof. For IP67 or higher applications, M8/M12 (industrial), Deutsch DT (automotive), or sealed proprietary connectors are better. See our waterproof harness page.
- High-frequency signaling: JST connectors are general-purpose; for RF, USB, HDMI, DisplayPort, or other high-speed signaling, dedicated high-speed connectors are required.
- Mating cycle requirements: JST friction-fit connectors are rated for limited mating cycles (typically 10-50). For applications requiring frequent disconnection (test fixtures, repair-friendly designs), connectors rated for higher mating cycle counts are appropriate.
A Common Mistake — Overusing PH
The most frequent JST spec error we see is PH being used everywhere out of habit. PH is great for general signal and low-power connections, but it’s not great in vibration environments (use XH), in compact form factors (use SH or GH), in lithium battery balance applications (use EH), or in higher-current applications (use NH, VH, or step over to Molex MicroFit). Defaulting to PH because the engineering team is familiar with it can cost reliability or space.
The opposite mistake — over-specifying to a higher series than needed — is less common but happens. Specifying NH (10A rating) for a 1A signal application wastes board space and cost. Match the family to the actual current and form factor requirement.
Bottom Line
JST connector selection comes down to four primary families covering 80% of consumer and small-electronics applications. PH for general PCB-to-wire signal and low-power. XH when current is higher or vibration is a concern. SH for compact form factors. EH for small lithium battery balance leads. Adjacent series (GH, ZH, NH, VH) extend the catalog into specific niches. Matching family to application gets you reliable connections at appropriate cost without over-engineering or under-engineering.
Related Reading
- JST Connector Harness — full JST family scope and assembly capabilities.
- Molex Connector Harness — alternative connector ecosystem for higher current.
- Waterproof Wire Harness — sealed connector alternatives for IP-rated applications.
- Consumer Electronics Solutions — JST applications across consumer products.
- Cable Insulation Material Guide — companion guide on jacket selection.
Need Help Picking the Right JST Family?
Send us your application — current, pin count, mating cycles, vibration, and form factor constraints. We’ll match the JST family or recommend an alternative connector if JST isn’t the best fit.