USB Power Delivery 3.1: EPR 240W & PPS Programming Guide

Specification Details & Pinouts

USB Power Delivery 3.1: EPR 240W & PPS Programming Guide

USB PD 3.1 (released May 2021) extends the power delivery ceiling from 100W to 240W via Extended Power Range (EPR), enabling high-performance laptops, gaming systems, and professional displays to charge over a single USB-C cable.

Power Profiles Comparison

Profile	Voltage	Current	Power	Use Case
SPR 5V	5.0V	3A	15W	Mobile phones, accessories
SPR 9V	9.0V	3A	27W	Tablets, small laptops
SPR 15V	15.0V	3A	45W	Ultrabooks
SPR 20V	20.0V	5A	100W	High-performance laptops
EPR 28V	28.0V	5A	140W	Gaming laptops
EPR 36V	36.0V	5A	180W	Workstations
EPR 48V	48.0V	5A	240W	Desktop replacement, displays

PPS (Programmable Power Supply) Operation

PPS enables step-wise voltage adjustment from 3.3V to 21V in 20mV increments. This allows direct battery charging without intermediate DC-DC conversion, reducing heat and improving efficiency.

PPS Voltage Ranges

• SPR PPS: 3.3V – 5.9V (20mV steps), max 3A
• SPR PPS: 3.3V – 11.0V (20mV steps), max 3A
• SPR PPS: 3.3V – 16.0V (20mV steps), max 3A
• SPR PPS: 3.3V – 21.0V (20mV steps), max 3A
• AVS (EPR PPS): 15.0V – 48.0V (100mV steps), max 5A

EPR Entry Sequence

1. Source advertises EPR capability in Source_Capabilities message
2. Sink requests EPR mode via EPR_Request message
3. Source validates cable E-Marker (Vbus_max ≥ 48V, I_max ≥ 5A)
4. Source sends PS_RDY after voltage reaches EPR level
5. EPR mode active. Both sides monitor for faults every 500ms

Cable Requirements for 240W

Not all USB-C cables support 240W. Required specifications:

• E-Marker chip mandatory (reports 48V/5A capability)
• Insulation rating: ≥ 60V DC (EPR minimum)
• Wire gauge: ≥ 22AWG for Vbus and GND (to limit resistance)
• Connector housing: High-temperature polymer (≥ 105°C)
• Shielding: Double-layer braid + foil (for EMI at 48V)

Reference: USB PD Specification Rev 3.1 V1.7. USB Type-C Cable and Connector Specification Rev 2.2.