01
Pin Map and Contact Functions
Define the function of each power, return, signal, control or detection contact.
CTP 4 Pin Single Row 2.8mm Magnetic Pogo Pin Connector Pair combines four inline electrical contacts, a spring-loaded pogo pin side, a flat mating target side and magnetic structures positioned on both sides of the contact area. The four contacts can be assigned to power, return, detection, identification, control or project-specific signal functions according to the customer Pin Map. Final dimensions, 2.8mm dimensional definition, working stroke, current, voltage, magnetic retention, mating life and environmental performance must be confirmed using the approved product drawing and complete customer assembly.
Product specifications should be reviewed together with the customer device, PCB, electrical assignment and mechanical mating conditions.
Define the function of each power, return, signal, control or detection contact.
Provide voltage, continuous current, peak current and required signal conditions.
Provide available length, width, height, PCB area and required mating orientation.
Provide application, expected quantity, environment and customer validation requirements.
Review the product-specific description, technical parameters, contact arrangement, mechanical structure and project conditions below.
Engineering Summary: The CTP 4 Pin Single Row 2.8mm Magnetic Pogo Pin Connector Pair combines four inline electrical contacts, a spring-loaded pogo pin side, a flat mating target side and magnetic structures positioned on both sides of the contact region. The four contacts can be assigned to project-specific power, return, detection, identification, control or signal functions. Final dimensions, the exact definition of the 2.8mm parameter, working stroke, electrical ratings, magnetic retention, mating life and environmental performance must be confirmed using the approved product drawing and complete customer assembly.
This 4 pin magnetic pogo pin connector uses four electrical contact positions arranged in a compact single row. One connector half contains spring-loaded pogo pin contacts, while the opposing half provides corresponding flat mating targets.
Magnetic structures positioned beside the contact region can assist connector capture and seated attachment. Final electrical alignment and pogo pin compression should still be controlled through the connector housing, mating surfaces and mechanical stops.
The 2.8mm dimension should be clearly defined in the approved product drawing. If it represents contact pitch, it should be specified as the center-to-center distance between adjacent electrical contacts.
| Connector Element | Product Structure | Engineering Requirement |
|---|---|---|
| Contact Count | Four electrical contacts | Define the electrical function of every contact |
| Contact Arrangement | Single-row inline layout | Confirm contact position and center distance using the drawing |
| Pogo Pin Side | Four spring-loaded electrical contacts | Define free height, working stroke and contact force |
| Target Side | Four flat mating targets | Define target size, material, finish and flatness |
| Magnetic Structure | Magnetic regions located beside the contact array | Define capture, seated retention and separation requirements |
| Housing | Compact elongated insulating housing | Confirm overall dimensions and device installation envelope |
| Mounting Features | Side structural features visible on the housing | Confirm locating or mounting function using the approved drawing |
A dimensional value such as 2.8mm is useful only when its engineering definition is clear.
If 2.8mm represents contact pitch, pitch is normally defined as:
the center-to-center distance between adjacent electrical contacts.
Contact pitch affects:
The drawing should identify whether 2.8mm refers to contact pitch, mounting spacing, housing dimensions or another mechanical parameter.
Four contact positions do not represent one universal electrical architecture. Each contact should be assigned according to the customer schematic.
Possible functions include:
| Architecture | Example Contact Allocation | Primary Engineering Review |
|---|---|---|
| Power + Detection + Identification | Power, return, detection and identification | Power-enable sequence and accessory recognition |
| Power + Control | Power pair plus two project-specific control contacts | Logic voltage, reference path and fault protection |
| Parallel Power | Two positive contacts and two return contacts | Current sharing, voltage drop and temperature rise |
| Power + Two Signals | Power, return and two project-specific signal contacts | Signal reference, interference and reconnection behaviour |
These are examples only. The final Pin Map must be developed from the customer circuit.
If 2.8mm is the contact pitch, it describes geometric spacing rather than current, voltage or data performance.
Current capability depends on the complete electrical path, including:
The nominal contact spacing is only one part of the mating geometry. Positional tolerances of the pogo pins and mating targets must also be included.
The dimensional review should consider:
The worst-case stack should confirm that each pogo pin remains within its intended target area.
Magnetic attraction can assist the connector during approach, but magnets should not be the only elements determining the final electrical position.
| Interface Function | Recommended Control |
|---|---|
| Initial Capture | Magnetic layout and approach geometry |
| Orientation | Housing geometry and magnetic polarity |
| Final Alignment | Mechanical datums and mating surfaces |
| Pogo Pin Compression | Mechanical stops and dimensional tolerance stack |
| Seated Retention | Magnetic structure and customer mechanical support |
| Connector Removal | Defined separation direction and release-force requirement |
Capture force, seated retention and separation force should be measured separately because they describe different connector behaviours.
Each spring-loaded contact must remain inside its approved compression range when the connector reaches the final seated position.
A simplified working-stroke relationship is:
S = Hfree - Hseated
where:
The tolerance stack may include:
| Stroke Condition | Possible Result |
|---|---|
| Insufficient Compression | Intermittent power, unstable signal or resistance variation |
| Approved Working Stroke | Intended contact force and electrical condition |
| Excessive Compression | Spring bottoming, target damage or excessive housing load |
| Unequal Compression | Different resistance between the four contacts |
Connector current capability cannot be determined from four contacts or 2.8mm spacing alone.
A simplified complete-path resistance is:
Rpath = Rhost-PCB + Rtermination1 + Rpogo + Rinterface + Rtarget + Rtermination2 + Rdevice-PCB
The voltage drop is:
Vdrop = I × Rpath
The resistive power loss is:
Ploss = I² × Rpath
The project should define:
If two contacts are connected in parallel for positive power and two for return, the current may not divide equally.
Current sharing can be affected by:
Individual contact current and temperature should be evaluated under the maximum intended electrical load.
A four-contact magnetic connector provides four conductive paths, but the connector does not automatically support USB, UART, I2C or another communication protocol.
The complete signal channel may include:
Host Controller → Host PCB → Protection Components → Magnetic Connector → Device PCB → Device Controller
Signal capability depends on:
Magnetic attraction may retain the two connector halves close together before all four contacts reach their intended working stroke.
| Condition | Possible Risk | Required Review |
|---|---|---|
| One End Contacts First | Unexpected power or signal sequence | Approach angle and contact-height tolerance |
| Only Some Contacts Are Seated | Partial power or incorrect detection state | Pin Map and full-seating logic |
| Laterally Offset Mating | Pogo pin reaches the wrong target | Pitch, target dimensions and maximum credible offset |
| Magnetically Retained but Not Fully Seated | Unstable electrical connection | Mechanical stop and full-seating verification |
| Wrong Orientation | Incorrect Pin Map or polarity condition | Housing coding and magnetic polarity |
| Removal Under Load | Transient voltage, arcing or signal interruption | Power-disable sequence and powered-endurance testing |
| Parameter | Product Definition |
|---|---|
| Product Type | 4 pin single row magnetic pogo pin connector pair |
| Contact Count | Four electrical contacts |
| Contact Arrangement | Single-row inline layout |
| 2.8mm Dimension | Confirm exact dimensional definition using the approved drawing |
| Contact Pitch | Use 2.8mm only when confirmed as center-to-center contact spacing |
| Mating Structure | Spring-loaded pogo pin side with corresponding flat target side |
| Pin Map | Project-specific power, return, detection, identification, control and signal allocation |
| Overall Dimensions | Confirm using the approved mechanical drawing |
| Working Stroke | Confirm minimum, nominal and maximum compression |
| Contact Force | Report at a defined working stroke |
| Voltage | Model- and circuit-specific |
| Continuous Current | Confirm through voltage-drop and temperature-rise testing |
| Contact Resistance | Report with test current, target, stroke and measurement method |
| Magnetic Performance | Capture, seated retention and separation force are specified separately |
| Mating Life | Defined by working stroke, electrical load and acceptance criteria |
| Environmental Protection | Applies only to a defined and tested connector or complete assembly |
| Application | Possible Connector Role | Primary Engineering Focus |
|---|---|---|
| Consumer Electronics | Power, charging, detection or control connection | Compact size and repeated mating |
| Smart-Home Devices | Docking or removable module interface | Pin Map and mechanical integration |
| Portable Electronics | Power and project-specific signal connection | Retention and electrical protection |
| Industrial Handheld Devices | Charging, control or service interface | Vibration and contact stability |
| Charging Docks | Power, detection, identification and control | Alignment and partial mating |
| Custom Electronic Modules | Project-specific four-contact interface | Contact spacing and housing integration |
These applications are examples. Final suitability depends on the Pin Map, electrical load, available space and complete device validation.
| Input | Information to Provide |
|---|---|
| Pin Map | Function of all four electrical contacts |
| 2.8mm Definition | Confirm whether 2.8mm represents contact pitch or another dimension |
| Electrical Conditions | Voltage, continuous current, peak current and signal types |
| Available Space | Maximum length, width, height and restricted regions |
| Working Stroke | Minimum, nominal and maximum pogo pin compression |
| Mating Direction | Approach, final seating and removal direction |
| Termination | PCB, FPC, wire or project-specific connection |
| Magnetic Requirement | Capture, seated retention and separation conditions |
| Environment | Temperature, moisture, dust, vibration and cleaning exposure |
| Project Files | 2D drawing, 3D model, schematic, PCB layout or device assembly |
It is a magnetic spring-contact connector with four electrical contacts arranged in one row. The contacts can be assigned to project-specific power, return, detection, identification, control or signal functions.
The exact definition should be confirmed using the approved product drawing. If 2.8mm represents contact pitch, it describes the center-to-center distance between adjacent contacts.
Contact pitch affects mating-target positioning, PCB layout, connector size, positional tolerance and the risk of an adjacent-contact mismatch during offset mating.
Yes. Different contacts can be assigned to project-specific power and signal functions according to the customer Pin Map and complete circuit design.
No. Current capability depends on contact geometry, working stroke, mating targets, termination, PCB routing and thermal conditions.
No. Pin count alone does not establish USB or another communication protocol. Complete channel design and validation are required.
No universal rating should be assumed. Current and voltage must be confirmed for the exact connector structure and complete customer assembly.
No. An ingress-protection rating must apply to a defined and tested connector or complete device assembly under stated conditions.
Provide the four-contact Pin Map, definition of the 2.8mm dimension, voltage, current, available space, working stroke, magnetic requirements and available project drawings.
Review additional custom magnetic connector components for different pin counts, contact spacing and mating structures.
Submit the Pin Map, 2.8mm dimensional requirement, electrical conditions and available drawings through the Get Quote & Samples page .
CTP can review the four-contact single-row layout, contact spacing, pogo pin working stroke, mating targets, magnetic structure, housing and PCB, FPC or wire termination. Final electrical ratings, signal capability, magnetic retention, mating life and environmental performance must be confirmed through approved drawings and project-specific validation.
This product page presents a CTP magnetic connector configuration for engineering reference. Final dimensions, electrical ratings, materials, magnet structure, sealing level and reliability targets are not universal values; they are confirmed against the approved drawing, installation condition and model-specific validation plan.
CTP reviews the application and prepares a drawing or specification for approval before sample production. Test scope, acceptance criteria and report format should identify the model, sample status, method, conditions, result and review date.
Yes. Customization can cover geometry, contact layout, materials, cable construction, magnetic structure, sealing and appearance. Feasibility depends on the application and approved specification.
No. Current, voltage, resistance, temperature rise and ingress-protection claims apply only to the identified model and stated test conditions.
Timing is confirmed after the drawing, materials, tooling, sample quantity, validation scope and production requirements have been reviewed.
Submit your Pin Map, electrical requirements, available space, mating structure and project quantity for connector selection or custom development review.
Use the following engineering guides to compare contact count, contact allocation and connector layout before confirming the final product or customized design.
Review the complete selection path from contact count and electrical functions to connector shape.
View Main Guide →Compare one-contact special structures, complete two-contact circuits and third-contact functions.
Compare Low-Pin Designs →Determine whether four contacts are sufficient or whether a defined fifth electrical path is required.
Compare 4 Pin and 5 Pin →Calculate the contact budget and compare six-contact, multi-row and customized contact-array structures.
Compare High-Pin Designs →
