JST BHS Connector: Complete Guide to 3.5mm SMT Wire-to-Board, Wire-to-Wire, High-Voltage LCD Backlight Specs & Part Numbers
The JST BHS connector solves a problem that most 3.5mm pitch connectors cannot: high-voltage wire termination in an SMT, low-profile package. While the JST XH, EH, and SM series are all rated at 250V AC/DC, the BHS is rated at 1,400V AC/DC (wire-to-board) and 1,900V AC/DC (wire-to-wire) — with a withstanding voltage of 3,800V AC/minute. This makes the BHS the connector of choice for applications where standard 250V wire-to-board connectors are insufficient: LCD backlight lamp connections, CCFL inverter wiring, and other low-current, high-voltage signal and power circuits.
Despite its specialized capabilities, the BHS is almost entirely undocumented outside of the JST datasheet. This guide covers everything: the two BHS variants (SMT wire-to-board and wire-to-wire), complete electrical specifications, all housing and contact part numbers with their decoding, PCB layout for the SMT header, and a direct comparison with other JST connectors in the 3.5mm pitch family.
What Is the JST BHS Connector? Two Variants, One System
The JST BHS series exists in two distinct configurations that share the same 3.5mm pitch and high-voltage rating but serve different connection types:
BHS Wire-to-Board (SMT): The primary BHS configuration. A wire-side receptacle housing (BHSR-02VS-1) mates with an SMT PCB header (SM02B-BHSS-1-TB). The header is surface-mount (SMT) with solder tabs and solder tails — no through-hole drilling required. This is the configuration used when connecting a wire harness to a PCB in a low-profile, high-voltage application.
BHS Wire-to-Wire: A second BHS configuration designed specifically for connecting liquid crystal display backlight lamps to their starters. Two wire housings mate directly — no PCB header. The wire-to-wire version uses a different contact set (SBHSM-002T-P0.5 pin + SBHS-003T-P0.5A socket) and achieves an even higher voltage rating of 1,900V AC/DC.
Four features define the BHS across both variants:
1. High voltage rating in a compact 3.5mm pitch package
1,400V AC/DC (wire-to-board) and 1,900V AC/DC (wire-to-wire) — far exceeding the 250V rating of JST XH, EH, SM, and most other JST wire-to-board connectors. The 3,800V AC/minute withstanding voltage is significantly higher than the XH (1,500V) and EH (800V).
2. SMT configuration (wire-to-board version)
The SM02B-BHSS-1-TB header is surface-mount, with solder tabs on the PCB contact side and solder tails for mechanical retention. This enables use on thin PCBs where through-hole drilling is not possible or desirable, and supports reflow soldering in automated assembly.
3. Low profile design
The BHS housing is designed for low-profile applications. The wire-to-board assembly height is minimized compared to through-hole alternatives at the same pitch, making it suitable for slim LCD modules, inverter boards, and compact consumer electronics.
4. Housing lock as polarizing device
The BHSR-02VS-1 receptacle housing lock serves a dual function: it secures the mated connection and acts as a polarizing device — preventing incorrect orientation during mating. In high-voltage applications where reverse polarity can cause damage, this built-in mis-mating prevention is a critical safety feature.
JST BHS Electrical Specifications
| Parameter | BHS Wire-to-Board (SMT) | BHS Wire-to-Wire |
|---|---|---|
| Pitch | 3.5mm | 3.5mm |
| Connection type | Wire-to-board (SMT) | Wire-to-wire |
| Circuit count | 2 only | 2 only |
| Current rating | 1.0A AC/DC (AWG #24) | 1.0A AC/DC |
| Voltage rating | 1,400V AC/DC | 1,900V AC/DC |
| Temperature range | -25°C to +85°C | -25°C to +85°C |
| Contact resistance (initial) | 10mΩ max. | 10mΩ max. |
| Contact resistance (after environmental test) | 20mΩ max. | 20mΩ max. |
| Insulation resistance | 1,000MΩ min. | 1,000MΩ min. |
| Withstanding voltage | 3,800V AC/minute | 3,800V AC/minute |
| Applicable wire gauge | AWG #28 to AWG #24 | AWG #28 to AWG #24 |
| Conductor cross-section | 0.08 to 0.22 mm² | 0.08 to 0.22 mm² |
| Insulation O.D. (socket contact) | 0.9 to 1.7mm | 0.9 to 1.7mm |
| Insulation O.D. (pin contact) | N/A (SMT header) | 0.9 to 1.8mm |
| Contact structure | Wide large socket contact | Wide large socket contact |
| Header type | SMT (solder tabs + solder tails) | N/A (wire-to-wire) |
| Housing material | PA 66, UL94V-0, natural (white) | PA 66, UL94V-0, natural (white) |
| Contact material | Phosphor bronze, tin-plated (reflow treatment) | Phosphor bronze, tin-plated (reflow treatment) |
| UL recognition | E60389 | E60389 |
| CSA certification | LR20812 | LR20812 |
| RoHS compliance | Yes | Yes |
Critical note on voltage rating: The BHS wire-to-board version is rated at 1,400V AC/DC — more than 5× the voltage rating of JST XH, EH, SM, and most other JST 3.5mm connectors (250V). The wire-to-wire version reaches 1,900V AC/DC. Both versions share a withstanding voltage of 3,800V AC/minute.
Note on current rating: The BHS is rated at 1.0A AC/DC — lower than the 3A rating of JST XH, EH, SM, and RCY. The BHS is designed for low-current, high-voltage applications. Do not use the BHS for power connections requiring more than 1.0A continuous.
JST BHS Wire-to-Board (SMT): Part Numbers
Contact: SBHS-002T-P0.5A
The wire-side crimp contact for the BHS wire-to-board system. Inserts into the BHSR-02VS-1 receptacle housing.
| Part Number | Type | Wire Gauge (AWG) | Conductor (mm²) | Insulation O.D. (mm) | Material | Qty/Reel |
|---|---|---|---|---|---|---|
| SBHS-002T-P0.5A | Socket contact (strip form) | #28 to #24 | 0.08–0.22 | 0.9–1.7 | Phosphor bronze, Sn-plated (reflow) | 10,000 |
Part number decoding — SBHS-002T-P0.5A:
- S = Strip form
- BHS = Series name
- 002 = Applicable wire range: AWG #28 to AWG #24
- T = Surface finish: tin-plated (reflow treatment)
- P = Material: phosphor bronze
- 0.5 = Terminal size
- A = Shape: Type A
Crimping equipment: AP-K2N crimping machine. Contact JST for fully automatic crimping applicator details for SBHS-002T-P0.5A.
Housing: BHSR-02VS-1(N)
| Part Number | Type | Circuits | Color | Material | Qty/Bag |
|---|---|---|---|---|---|
| BHSR-02VS-1(N) | Receptacle housing (wire side) | 2 | Natural (white) | PA 66, UL94V-0 | 1,000 |
Part number decoding — BHSR-02VS-1(N):
- BHS = Series name
- R = Part name: Receptacle
- 02 = No. of circuits: 2-circuit only
- V = Flammability: UL94V-0
- S = Color: Natural (white)
- 1 = Shape: With protrusion (housing lock / polarizing device)
- (N) = Sub model number
SMT Header: SM02B-BHSS-1-TB
| Part Number | Type | Circuits | Color | Post material | Wafer material | Solder tab material | Qty/Reel |
|---|---|---|---|---|---|---|---|
| SM02B-BHSS-1-TB | SMT PCB header | 2 | Natural (ivory) | Brass, Cu-undercoated, Sn-plated (reflow) | PPA, UL94V-0, natural (ivory) | Brass, Cu-undercoated, Sn-plated (reflow) | 1,000 |
Part number decoding — SM02B-BHSS-1-TB:
- SM = Shape: SMT side entry type
- 02 = No. of circuits: 2-circuit only
- B = Part name: Header
- BHS = Series name
- S = Color: Natural (ivory)
- 1 = Shape: Without boss
- TB = Packaging: Embossed taping (pick-and-place compatible)
SMT header assembly notes: Supplied on embossed tape for pick-and-place automated assembly. Features solder tabs (PCB pad contact) and solder tails (mechanical retention). Reflow soldering compatible. LF×SN label indicates lead-free tin plating.
JST BHS PCB Layout (SMT Wire-to-Board)
- Pitch: 3.5mm between contact centers
- Solder tab footprint: 10.5mm total width across both tabs
- Header body width: 8.7mm
- PCB pad pattern: Refer to JST datasheet — tolerances non-cumulative ±0.1mm for all centers
- Assembly height: Low profile — side-entry (SM prefix), wire exits parallel to PCB surface
- Solder tail length: 13.9mm (for mechanical retention)
PCB design notes:
- Side-entry type (SM prefix) — wire exits parallel to the PCB surface
- Ensure adequate creepage and clearance distances for 1,400V operation — standard 250V PCB design rules are insufficient
- Embossed tape packaging (TB suffix) compatible with standard pick-and-place equipment
- Reflow solder profile: follow JST’s general instruction for tin-plated (reflow treatment) contacts
JST BHS Wire-to-Wire: Part Numbers
The wire-to-wire BHS version connects two wire harnesses directly — no PCB header. Designed specifically for LCD backlight lamp-to-starter connections.
Contacts
| Part Number | Type | Housing | Wire Gauge (AWG) | Conductor (mm²) | Insulation O.D. (mm) | Qty/Reel |
|---|---|---|---|---|---|---|
| SBHSM-002T-P0.5 | Pin contact | BHSMR-02VS (receptacle) | #28 to #24 | 0.08–0.22 | 0.9–1.8 | 5,000 |
| SBHS-003T-P0.5A | Socket contact | BHSR-02VS-1(N) (socket housing) | #28 to #24 | 0.08–0.22 | 0.9–1.7 | 10,000 |
Housings (Wire-to-Wire)
| Part Number | Type | Circuits | Material | Qty/Bag |
|---|---|---|---|---|
| BHSMR-02VS | Receptacle housing (for SBHSM-002T-P0.5 pin contact) | 2 | PA 66, UL94V-0, natural (white) | 1,000 |
| BHSR-02VS-1(N) | Socket housing (for SBHS-003T-P0.5A socket contact) | 2 | PA 66, UL94V-0, natural (white) | 1,000 |
Wire-to-wire mating rule: BHSMR-02VS (with SBHSM-002T-P0.5 pin contacts) mates with BHSR-02VS-1(N) (with SBHS-003T-P0.5A socket contacts). Total mated assembly length: approximately 21.4mm.
Crimping equipment (wire-to-wire contacts):
- SBHSM-002T-P0.5 (pin): AP-K2N machine, MKS-L dies, MK/SBHSM-002-05 applicator; APLMK SBHSM002-05
- SBHS-003T-P0.5A (socket): AP-K2N machine, MKS-L dies, MK/SBHS-002-05 applicator; APLMK SBHS002-05
JST BHS vs Other JST Connectors: High-Voltage Comparison
| Series | Pitch | Type | Current | Voltage Rating | Withstanding Voltage | Circuits | Header Type | Best For |
|---|---|---|---|---|---|---|---|---|
| JST BHS (W-B) | 3.5mm | Wire-to-board | 1.0A | 1,400V AC/DC | 3,800V AC/min | 2 only | SMT | LCD backlight, CCFL inverter, high-voltage signal |
| JST BHS (W-W) | 3.5mm | Wire-to-wire | 1.0A | 1,900V AC/DC | 3,800V AC/min | 2 only | N/A | LCD backlight lamp-to-starter |
| JST XH | 2.5mm | Wire-to-board | 3A | 250V AC/DC | 1,500V AC/min | 2–16 | Through-hole | General W-B, Arduino, 3D printers |
| JST EH | 2.5mm | Wire-to-board | 3A | 250V AC/DC | 800V AC/min | 2–15 | Through-hole + SMT | High-density PCB, fine wire, 10 colors |
| JST SM | 2.5mm | Wire-to-wire | 3A | 250V AC/DC | 1,500V AC/min | 2–18 | N/A | Wire harness, panel mount, arm lock |
| JST RCY (SYP) | 2.5mm | Wire-to-wire | 3A | 250V AC/DC | 1,500V AC/min | 2 only | N/A | RC batteries, sensors, free spring |
Key insight: If your application requires more than 250V AC/DC in a disconnectable crimp connector, the JST BHS is the correct choice in the JST lineup. No other standard JST disconnectable crimp connector in the 2.5–3.5mm pitch range achieves the BHS voltage rating.
➡️ JST XH 2.5mm Complete Guide → | JST EH 2.5mm Complete Guide → | JST SM Wire-to-Wire Guide → | JST RCY/SYP Guide →
JST BHS Applications: LCD Backlight and High-Voltage Signal Wiring
- LCD CCFL backlight connections — Cold cathode fluorescent lamps (CCFL) operate at high voltages (600V–1,500V AC) generated by inverter circuits. The BHS wire-to-wire version (1,900V rated) provides the necessary voltage isolation between the inverter output and the lamp connection.
- LCD LED backlight driver connections — High-voltage LED driver circuits for LCD backlighting require connectors rated above 250V. The BHS SMT wire-to-board version (1,400V rated) connects the driver PCB to the LED strip harness.
- CCFL inverter board connections — The SMT header (SM02B-BHSS-1-TB) mounts directly on the inverter PCB; the receptacle housing (BHSR-02VS-1) connects to the CCFL lamp wire leads.
- High-voltage signal lines in consumer electronics — Any application requiring a disconnectable 2-wire connection at voltages between 250V and 1,400V (wire-to-board) or 1,900V (wire-to-wire) where a compact, low-profile connector is needed.
- Thin notebook and monitor LCD assemblies — The low-profile SMT design and compact 3.5mm pitch suit the space constraints of laptop LCD modules and flat panel monitor backlight assemblies.
How to Select the Right JST BHS Configuration
- Determine connection type — Wire to PCB: use BHS wire-to-board (SMT) with SM02B-BHSS-1-TB header + BHSR-02VS-1 housing + SBHS-002T-P0.5A contact. Wire to wire: use BHS wire-to-wire with BHSMR-02VS + BHSR-02VS-1(N) housings + SBHSM-002T-P0.5 pin + SBHS-003T-P0.5A socket contacts.
- Verify voltage requirement — Wire-to-board: up to 1,400V AC/DC. Wire-to-wire: up to 1,900V AC/DC. Both: 3,800V AC/minute withstanding.
- Confirm current requirement — 1.0A maximum continuous (AWG #24). For higher current, use JST XH, EH, or SM (3A rated) instead.
- Verify wire gauge — AWG #28 to #24 (0.08–0.22mm²). Insulation O.D.: 0.9–1.7mm (socket contact) / 0.9–1.8mm (pin contact).
- Confirm SMT compatibility — The wire-to-board header (SM02B-BHSS-1-TB) is SMT only. If your PCB requires through-hole mounting, the BHS wire-to-board version is not compatible.
- Check PCB creepage/clearance — At 1,400V operation, PCB layout must comply with applicable safety standards (IEC 60950, IEC 62368, or equivalent). Standard 250V PCB design rules are insufficient.
➡️ Shop JST BH 3.5mm pre-crimped cable assemblies: JST BH 3.5mm Cable Assemblies — Male/Female Single-Head, Same-Side-Head & Extension, 22AWG UL1007, 1.0A/1,400V →
➡️ Individual cable variants: Male Single-Head | Female Single-Head | Male Same-Side-Head | Female Same-Side-Head | Male-Female Extension
Frequently Asked Questions
What is the JST BHS connector?
The JST BHS is a 3.5mm pitch disconnectable crimp connector available in two versions: a wire-to-board SMT version (1,400V AC/DC, SM02B-BHSS-1-TB header + BHSR-02VS-1 housing) and a wire-to-wire version (1,900V AC/DC, BHSMR-02VS + BHSR-02VS-1 housings). Both are rated at 1.0A, -25°C to +85°C, 3,800V withstanding voltage, AWG #28–#24. UL E60389, CSA LR20812, RoHS compliant. Designed for LCD backlight lamp connections and high-voltage signal wiring.
What voltage is the JST BHS connector rated for?
The JST BHS wire-to-board (SMT) version is rated at 1,400V AC/DC. The wire-to-wire version is rated at 1,900V AC/DC. Both versions have a withstanding voltage of 3,800V AC/minute. This is significantly higher than most JST connectors (XH, EH, SM: 250V AC/DC) and makes the BHS the correct choice for CCFL backlight, inverter, and other high-voltage low-current applications.
What is the SM02B-BHSS-1-TB?
The SM02B-BHSS-1-TB is the SMT PCB header for the JST BHS wire-to-board system. It is a 2-circuit, side-entry SMT header with solder tabs and solder tails, supplied on embossed tape (TB suffix) for pick-and-place automated assembly. It mates with the BHSR-02VS-1(N) receptacle housing loaded with SBHS-002T-P0.5A contacts. Material: PPA wafer (UL94V-0, ivory), brass posts and solder tabs, tin-plated (reflow treatment).
What is the BHSR-02VS-1 housing?
The BHSR-02VS-1(N) is the wire-side receptacle housing for the JST BHS system. It accepts SBHS-002T-P0.5A socket contacts (wire-to-board) or SBHS-003T-P0.5A socket contacts (wire-to-wire). Material: PA 66, UL94V-0, natural (white). The housing lock serves as both a retention mechanism and a polarizing device to prevent mis-mating. 2-circuit only, 1,000 per bag.
What is the difference between SBHS-002T-P0.5A and SBHS-003T-P0.5A?
Both are JST BHS socket contacts in strip form, phosphor bronze, tin-plated. SBHS-002T-P0.5A is used in the wire-to-board system (inserts into BHSR-02VS-1 for mating with SM02B-BHSS-1-TB header), supplied 10,000/reel. SBHS-003T-P0.5A is used in the wire-to-wire system (inserts into BHSR-02VS-1(N) socket housing for mating with BHSMR-02VS receptacle), supplied 10,000/reel. Do not interchange these contacts between systems without verifying compatibility with JST.
Can the JST BHS be used for applications other than LCD backlights?
Yes. While the BHS was designed for LCD backlight lamp connections, its 1,400V–1,900V rating and compact 3.5mm SMT format make it suitable for any low-current (max 1.0A), high-voltage (up to 1,400V wire-to-board or 1,900V wire-to-wire) 2-wire connection requiring a disconnectable crimp connector. Applications include CCFL inverter outputs, high-voltage sensor connections, piezoelectric actuator wiring, and other specialized circuits where standard 250V connectors are insufficient.
Is the JST BHS RoHS compliant?
Yes. The JST BHS series is RoHS compliant. The SM02B-BHSS-1-TB header displays the LF×SN label indicating lead-free tin plating. The SBHS-002T-P0.5A contact uses reflow-treatment tin plating (lead-free). UL Recognized E60389, CSA Certified LR20812.
➡️ JST XH Guide → | JST EH Guide → | JST SM Guide → | JST RCY/SYP Guide → | JST Connector Types → | Wire-to-Board Types →