Solution:
Root Cause: PPS (Programmable Power Supply) Protocol Absence
High-power smartphones (such as Samsung Galaxy S21–S24 series requiring 25W/45W Super Fast Charging 2.0) utilize a specialized subset of USB-PD 3.0 called
PPS (Programmable Power Supply). Unlike standard fixed USB-PD profiles (9V, 15V, 20V), PPS allows the phone to dynamically request granular micro-adjustments in voltage (e.g., 3.3V to 11V in 20mV steps) and current to feed the internal charge pump directly without generating excess heat inside the phone. If a 65W PD charger lacks explicit
PPS profile support, the phone rejects high-wattage fast charging and falls back to baseline 15W (5V/3A or standard 9V/1.67A) charging.
Diagnostic Verification:
1Inspect the technical specifications on the charger label. Look for explicit output lines labeled PPS: 3.3V-11.0V=4.05A or 3.3V-21.0V=2.25A.
2Connect the phone. If a 65W standard USB-PD charger only outputs 'Fast Charging' (15W) instead of 'Super Fast Charging 2.0' (45W), the charger lacks PPS capability.
Step-by-Step Fix:
1Acquire a PPS-Compliant USB-PD 3.0 Charger:
Purchase a power adapter explicitly stating USB-PD 3.0 with PPS (Programmable Power Supply) support.2Verify Amperage Rating for 45W+ Modes:
Ensure the charger's PPS profile supports at least 4.05A to 5A at sub-11V thresholds. A 65W charger rated for only 3A PPS will cap charging at 25W.3Pair with 5A e-Marked Cable:
Ensure you use a 5A-rated C-to-C cable to allow PPS current negotiation above 3A.Prevention & Long-Term Monitoring:
Always check for explicit 'PPS' protocol support when buying third-party GaN chargers for flagship devices.