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The World's Smallest Class Floating Board-to-Board Connector, 125°C heat resistance and high contact  reliability with two-point contacts  for automotive specifications

±0.4mm Floating Amount, Small Size with 3.8mm Width,
125℃ Head Resistance

Automotive Board to Board Connector BM54 Series

The BM54 series is a board-to-board connector that combines floating functionality and compact size to meet automotive specifications. It has a generous floating amount of ±0.4mm in the XY direction, yet is compact with 3.8mm width. Floating also improves assembly work efficiency by absorbing board misalignment.

Furthermore, its heat resistance of 125°C, which is required for in-vehicle equipment, makes it suitable for a wide range of applications including consumer and industrial equipment as well as front cameras, rear/side cameras, millimeter wave radar, and LiDAR, which are key components in automated driving.

BM54 Series Product Page

Example : Board-to-Board Connection in Automotive Camera

Example : Board-to-Board Connection in Automotive Camera


One of the World’s Smallest Width Dimensions

With a height of 3.0 mm, a contact pitch of 0.4 mm, and a width of 3.8 mm, the BM54 series is one of the world's smallest board-to-board connectors with a floating function. Compared to other companies' products, it occupies 34% less board space, contributing to the miniaturization of sets.
*In ±0.4mm floating board-to-board connector

Comparison of PCB Mounting Space

0.4mm pitch, 3.0mm Stacking Height, 30pos.

Comparison of PCB Mounting Space

Floating Range ±0.4mm in X and Y directions absorb PCB Misalignment

A floating design on the plug side allows ±0.4mm of movement in the XY axis direction. By absorbing misalignment when mounting the connector or assembling the board into the end of product, the design flexibility is expanded. It is also possible to mount and assemble multiple connectors on the same board. Contact reliability is also ensured with an effective mating length of up to 0.4 mm.

Plug Side

Floating Amount


Floating Amount

Effective Mating Length

±0.3mm (Stacking Height : 3.0mm)
±0.4mm (Stacking Height : 3.5 to 4.5mm)

Connector absorbs misalignment.

Connector absorbs misalignment.

Can Mount Multiple Connectors on One Board

Can Mount Multiple Connectors on One Board


Rated Current  0.3A
Rated Voltage 50V AC/DC
Operating Temperature -55 to +125℃
*Includes the temperature rising by current flow.
Contact Resistance

Initial : 80mΩ Max.     After the Test : 100mΩ Max.

Withstanding Voltage  100V AC for 1 min.
Insulation Resistance  100MΩ Min. (100V DC)
Mating Durability  10 times

Variations (As of October 2023)

Stacking Height (mm) 3.0 3.5 4.0 4.5
10pos. Under Planning
20pos. Under Planning
30pos. Mass Production Under Planning
40pos. Under Development Under Planning

Application ()

Applications such as Millimeter Wave Rader and LiDAR Supporting Automated Driving
Front Camera and Rear/Side Camera for Automotive
BM54 Series Product Page

Click here for other recommended connectors for autonomous driving.

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*In cases where the application will demand a high level of reliability, such as automotive, please contact a company representative for further information.

*The contents and specifications are subject to change.