Apple Watch Charging Puck Spec and Compatibility Workbench

Curated from @MacRumors • New Puck Revision Analysis

Charging Hardware Configuration

Simulate real USB-C Power Delivery handshake, magnetic coil specs, and thermal throttling limits.

20W
5W (USB-A) 18W 20W (Recommended) 65W+
22°C
15°C (Cool room) 22°C (Optimal) 35°C+ (Thermal Guard Active)
Fast Charging Handshake Active

USB-PD 9V/2.22A or 5V/3A negotiation successful. The aluminum enclosure on the Series 10 accommodates a larger secondary induction coil, sustaining up to 5.2W peak wireless transfer into the battery controller.

Real-Time Delivery & Thermal Telemetry

Modeled wattage taper curve and charging session time calculation.

Fast Charge Supported true USB-PD Negotiated
Peak Power Draw 5.2W 5.0V / 1.04A Inductive Equivalent
Est. Time to 80% Charge 30 min 0% to 80% High-Rate Stage
Thermal Management Status Optimal (Normal ambient operating range) Continuous Full-Speed Curve

Hardware Compatibility Matrix

Watch Model Fast Charge Capable 0–80% Duration (20W USB-C) Puck Requirement
Apple Watch Series 10 Yes (High Speed) ~30 mins Fast USB-C Puck
Apple Watch Ultra 1 / 2 Yes ~60 mins (564mAh) Fast USB-C Puck
Apple Watch Series 7 / 8 / 9 Yes ~45 mins Fast USB-C Puck
Apple Watch SE (1 / 2) Standard Only ~90 mins Any USB-C or USB-A Puck
Series 6 and older Standard (No PD) ~90–120 mins Any Magnetic Puck
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