OEM / ODM Custom Interconnect Solutions
High-Current Power Path Engineering

High-Current Magnetic Cable Solution Guide

CTP supplies custom high-current (3a – 10a+) for OEM and ODM device programs. Pin layout, geometry, materials, electrical requirements, sealing and validation.

Define the Operating Condition

A Current Number Alone Does Not Define a High-Current Cable

Begin with the complete operating condition. Continuous current, peak current, duty cycle, allowable voltage drop and ambient temperature determine how the cable and magnetic interface should be evaluated.

Continuous Current

Normal Operating Load

State the current that the cable must carry continuously during normal device operation.

Peak Current

Short-Term Maximum Load

State the peak current, its duration and how frequently the peak occurs during operation.

Duty Cycle

Load Timing Pattern

Define whether the load is continuous, intermittent, pulsed or part of a repeated charging cycle.

Voltage Budget

Allowable Electrical Loss

Define the source voltage, minimum device input and allowable voltage drop across the complete path.

“High current” should be tied to a stated cable length, contact allocation, ambient condition, mating state and validation method. A rating without these conditions is incomplete.
Complete Current Path

The Highest-Risk Point May Not Be the Magnetic Contact

Review every electrical and mechanical transition from the power source to the device and back through the return path.

01

Source Termination

Plug, adapter, bare wire, PCB joint or another source-side connection.

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02

Cable Conductors

Conductor length, structure, termination and movement condition.

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03

Magnetic Contacts

Contact allocation, alignment, compression and contact resistance.

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04

Device Connection

PCB pad, solder joint, FPC, internal wire or device terminal.

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05

Return Path

The complete return route must be included in resistance and temperature evaluation.

Optimizing only the pogo contact cannot compensate for an underspecified conductor, weak termination, unsuitable PCB trace or incomplete return path.
Power Contact Allocation

How Should Current Be Assigned Across the Contacts?

Choose the contact architecture according to the required current path, available space and complete circuit. Multiple contacts do not automatically share current equally.

Dedicated Pair

One Supply and One Return Path

Use a dedicated pair when each path can carry its assigned load within the agreed electrical, thermal and mechanical conditions.

Parallel Power Group

Multiple Contacts Assigned in Parallel

Parallel contacts may be evaluated when one path is distributed across multiple positions. Current sharing must be validated.

Power + Auxiliary

Separate Power and Control Groups

A multi-contact structure can separate high-current paths from detection, identification, control or customer-defined signal contacts.

ArchitectureMain BenefitMain RiskRequired Validation
Dedicated Supply and Return Clear assignment and straightforward continuity documentation. Each path carries its full assigned load. Loop resistance, voltage drop, temperature and mating stability.
Parallel Power Contacts Allows several contacts to participate in one power path. Resistance differences may create uneven current distribution. Individual contact condition, current sharing and partial mating.
Power and Auxiliary Channels Combines power delivery with defined control or signal functions. Incorrect grouping may affect the complete device system. Full Pin Map, cable map, circuit and device-level validation.
Two parallel contacts should not automatically be treated as carrying exactly half of the total current. Resistance, alignment, compression and contamination may create unequal current distribution.
Electrical Loss Budget

Calculate the Complete Loop Before Selecting the Cable

High-current performance depends on the combined resistance of the source termination, conductors, magnetic contacts, PCB connection and return path.

Total Loop Resistance
Rloop = ΣRpath

Add the resistance of every conductor, termination, contact and return connection.

Voltage Drop
Vdrop = I × Rloop

Compare the voltage drop with the minimum voltage required at the customer device.

Resistive Power Loss
Ploss = I² × Rloop

As current rises, power loss becomes more sensitive to resistance in the complete path.

Source Voltage
Nominal voltage and allowable range
Minimum Device Voltage
Lowest acceptable device input
Continuous Current
Normal steady operating current
Peak Current
Peak value, duration and frequency
Maximum Voltage Drop
Project-specific allowable loss
Measured Loop Resistance
Include temperature and mating condition
Maximum Ambient Temperature
Highest expected operating environment
Temperature Acceptance
Customer-defined acceptance criteria
Calculated values should be confirmed by measurement under agreed sample, load, ambient, mating and aging conditions.
Validation Matrix

Validate the Cable Under the Actual Current Profile

Sample approval should cover normal operation, peak loads, repeated mating and representative worst-case conditions.

Validation StageElectrical ConditionSample ConditionWhat to MeasurePurpose
Initial BaselineLow and normal loadNew, correctly mated sampleResistance, device voltage and temperatureEstablish the reference condition
Continuous LoadNormal continuous currentComplete cable and fixtureVoltage drop and temperature over timeConfirm steady-state performance
Peak LoadPeak current and duty cycleRepresentative operating sampleTransient voltage and heat accumulationConfirm intermittent operation
Partial MatingControlled safe test conditionIncomplete or offset connectionElectrical state and abnormal concentrationEvaluate possible mis-mating states
After Mating CyclesRepeat normal operating loadSample after defined cyclesResistance drift and temperatureCheck performance change with use
Environmental ReviewAgreed load conditionRequired ambient or exposure stateElectrical and thermal stabilityConfirm intended operating environment
Cable Flex ReviewNormal operating loadCable routed as in the deviceVoltage fluctuation and local temperatureVerify outlet and strain relief
Failure Diagnosis

Where Does the Temperature Rise Begin?

The location and timing of abnormal heat can help narrow the investigation to the contact, conductor, termination, PCB or operating condition.

Contact Area

Heat at the Magnetic Interface

Review contact resistance, alignment, compression, contamination and wear.

Cable Body

Heat Distributed Along the Cable

Review conductor length, cable structure, routing, ambient condition and load duration.

Termination

Heat at a Solder or Crimp Point

Review conductor preparation, joint area, soldering, crimping and local strain.

Parallel Contact

One Contact Is Hotter Than the Others

Review unequal resistance, mating tolerances and whether current is actually being shared.

Cable Movement

Heating Appears After Bending

Review conductor damage, outlet structure, strain relief and local resistance change.

Mating Aging

Heating Increases After Repeated Use

Compare resistance and temperature with the initial sample baseline.

Record measurement location, ambient temperature, current profile, sample state, mating condition and test duration for every temperature result.
Project Specification Worksheet

Information Required Before High-Current Development

Complete the electrical, cable, connector and validation information before selecting a product or developing a customized structure.

Application / Device
Equipment and operating function
Supply Scope
Connector or finished cable assembly
Source Voltage
Nominal and allowable range
Device Input
Required and minimum acceptable voltage
Continuous Current
Normal steady current
Peak Current
Value, duration and frequency
Power Contact Allocation
Supply, return and parallel groups
Auxiliary Contacts
Detection, control or signal functions
Cable Length
Total length and tolerance
Source Interface
Plug, wire, PCB or custom termination
Installation Space
Length, width, height and mating area
Operating Environment
Temperature, moisture and vibration
Cable Movement
Fixed, bending or repeated movement
Validation Criteria
Electrical and thermal acceptance
Expected Quantity
Prototype and production quantity
Available Drawings
Circuit, PCB, cable and housing drawings
High-Current Magnetic Cable FAQ

High-Current Magnetic Connection Questions

What makes a magnetic cable a high-current cable?
A high-current cable should be evaluated against a defined continuous current, peak current, duty cycle, cable length, allowable voltage drop, ambient condition and temperature acceptance requirement.
Why should continuous and peak current be listed separately?
Continuous current defines the long-duration load. Peak current must also include its duration, repetition frequency and recovery interval.
Can several pogo contacts be connected in parallel?
Parallel power contacts may be evaluated, but equal current sharing should not be assumed. Resistance, alignment, tolerances and mating state must be validated.
Does a higher pin count automatically support more current?
No. Current capability depends on power-contact allocation, conductor design, termination, loop resistance, temperature and complete operating conditions.
How is voltage drop evaluated?
Evaluate the total loop resistance of the source termination, cable conductors, magnetic contacts, PCB connection and return path, then compare the result with the minimum voltage required at the device.
Why can a connector become hotter after repeated mating?
Investigation may include resistance drift, contact-surface condition, contamination, wear, alignment and compression.
Should temperature be measured only at the connector?
No. The source termination, cable body, strain relief, magnetic interface, PCB connection and return path should all be reviewed.
What information is required for a custom high-current cable?
Provide voltage, continuous and peak current, duty cycle, cable length, contact allocation, termination, installation space, environment, movement condition, validation requirements, quantity and drawings.
Electrical & Thermal Project Review

Define Your High-Current Magnetic Connection

Send the continuous and peak current, duty cycle, cable length, contact allocation, allowable voltage drop, ambient condition and available drawings.