4-Pin Magnetic Connector | Promax Pogo Pin

How to Choose the Right 4-Pin Magnetic Connector

A 4-pin magnetic connector is the most common pin count in our catalog. It handles VCC, GND, and a pair of data or signal lines — enough for USB-style charging, low-speed comms, and most accessory interfaces. Use the steps below to lock in current, signal, and housing specs.

1. Define how the four pins are split between power and signal. A common layout is two power pins (VCC + GND) and two signal pins (D+ / D−). Other applications run three power pins in parallel with a single sense line. Tell us the split and we’ll match contact spacing and shielding.
2. Match the per-contact current to your power budget. Our standard 4-pin parts handle up to 4A per contact at 12V. With two pins in parallel on the power side, total current capacity reaches 8A. Higher-current variants support fast-charge applications in the 25A+ total range.
3. Verify contact resistance for the power and data paths. Standard 4-pin connectors hold contact resistance at 50 mΩ or below per pin. That’s low enough for USB 2.0-compatible signal integrity and keeps power-side voltage drop minimal. For high-speed data, we offer tighter-tolerance variants.
4. Confirm the temperature and humidity range. Standard 4-pin parts run from –40°C to +85°C across 10%RH to 90%RH. That covers most automotive accessories, outdoor wearables, and industrial sensor applications without requiring a custom build.
5. Check the mechanical life rating against expected mate cycles. Standard 4-pin connectors are rated for 10,000 cycles. A wearable charged daily fits well inside that budget. For products with multiple mates per day, ask about extended cycle ratings during the quote.
6. Pick the housing geometry and magnet layout. With 32+ standard 4-pin SKUs already in our catalog, the chance of a stock part fitting your enclosure is high. If not, we customize contact pitch, magnet polarity, and housing diameter. Send a 3D model or DWG with the inquiry.
7. Confirm plating, materials, and certifications. Standard contacts use Gold plating over a copper alloy base. Promax holds ISO 9001, ISO 14001, ISO 45001, and IECQ QC080000, and all 4-pin connectors are RoHS-compliant. Thicker plating, Nickel plating, or alternative materials are available during custom design.

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