USB-C Power Delivery Explained — Wattages, Versions & Laptop Charging

USB-C Power Delivery is now the universal laptop charging standard, but the version numbers (2.0, 3.0, 3.1), wattage ratings, and voltage profiles can feel overwhelming. This guide cuts through the jargon to explain exactly what USB-C Power Delivery does, which version your laptop needs, and how to avoid buying an incompatible charger.

Whether you’re looking to replace a missing MacBook charger, upgrade to faster charging on a gaming laptop, or understand why some USB-C chargers work with your Dell but not your ThinkPad, understanding PD is essential.

What Is USB-C Power Delivery?

USB-C Power Delivery (often abbreviated PD or USB PD) is a protocol that allows USB-C cables and chargers to negotiate and deliver power up to 240 watts. Without PD, USB-C was limited to 15W (5V at 3A) — fine for phones, but far too little for laptops.

PD works by having the charger and the device “talk” to each other through the USB-C cable. The charger announces what power levels it can deliver (called Power Data Objects, or PDOs), and the laptop requests the highest wattage it can safely use. This negotiation happens automatically in milliseconds, the moment you plug in.

Before USB-C PD, every manufacturer had their own proprietary connector: Dell had barrel connectors, Apple had MagSafe, Lenovo had proprietary round connectors. USB-C PD promises a world where one charger works with multiple laptops — though real-world compatibility is more nuanced, as we’ll see.

USB-C Power Delivery Versions Explained

There are three major versions of USB-C Power Delivery. Most devices support PD 2.0 or 3.0, but gaming laptops requiring 140W+ power demand PD 3.1.

In practice, almost all modern laptops work fine with a PD 2.0 or 3.0 charger rated at 65W or higher. Only gaming laptops (17″ ASUS ROG, Alienware, MSI) and the 16″ MacBook Pro really benefit from 140W+ chargers.

Voltage and Wattage Profiles (PDOs)

When a USB-C PD charger advertises its capabilities, it lists a series of Power Data Objects (PDOs) — each one a combination of voltage and maximum current. Your laptop picks the highest PDO it supports.

Here’s the standard progression:

Key insight: A 65W charger is the sweet spot for most laptop users. It covers 20V/3.25A, which is enough for any non-gaming laptop. A 100W charger handles gaming laptops and future-proofs you. For anything above that, you’re buying specialized gaming equipment.

How USB-C PD Negotiation Works

When you plug a USB-C PD charger into a laptop, the negotiation happens automatically in just a few milliseconds. Here’s the step-by-step process:

1. Physical connection: You plug the USB-C cable into both the charger and the laptop.
2. Charger advertises capabilities: The charger transmits a list of PDOs (voltage/current combinations) it can deliver.
3. Laptop requests power: The laptop’s USB-C controller reads the list and requests the highest PDO that matches its needs. For example, a MacBook Pro 14″ will request 20V/5A (100W) if available, falling back to 20V/3.25A (65W) if the charger only offers that.
4. Voltage is set: The charger confirms and switches to the requested voltage.
5. Charging begins: Current flows at the negotiated power level.

This negotiation is smart and automatic. You don’t need to configure anything. However, it relies on three things working correctly:

• The charger must advertise the correct PDOs. A broken or counterfeit charger might advertise 100W but only deliver 45W.
• The cable must support the negotiated voltage. A cheap 5A-rated cable might overheat at 20V/5A.
• The laptop’s USB-C controller must recognize the charger. Rare compatibility issues occur here, especially with older laptops.

USB-C PD vs Standard USB Charging

Not all USB-C charging uses Power Delivery. Here’s how different USB charging standards compare:

Bottom line: Don’t buy a USB-C charger that doesn’t explicitly say “Power Delivery” or “USB PD”. A basic USB-C charger with no PD will charge your laptop extremely slowly (if at all) and won’t support voltage negotiation.

PPS (Programmable Power Supply) Explained

Programmable Power Supply (PPS), introduced in PD 3.0, is a refinement that allows continuous voltage adjustments rather than fixed steps. Instead of jumping from 5V to 9V to 15V to 20V, a PPS-capable charger can deliver any voltage between its minimum and maximum in 20mV increments.

For phones and tablets, PPS is genuinely useful because it allows the charger to deliver voltage in fine-tuned steps that match the battery’s internal resistance cycle by cycle. This reduces heat generation during fast charging and can extend battery lifespan.

For laptops, PPS makes less difference. Most laptop batteries just accept whatever voltage the charger offers (5V, 9V, 15V, or 20V). A PPS-capable charger is slightly future-proof, but don’t pay extra for it unless you’re also charging high-end phones.

To check if a charger supports PPS, look for the phrase “Programmable Power Supply” in the specifications or contact the manufacturer.

USB-C PD Cable Requirements

Not all USB-C cables are created equal. The cable is just as important as the charger — a thin, cheap cable can overheat and fail when carrying high wattages.

The emark chip is essential. It’s a tiny circuit inside the cable connector that identifies the cable’s maximum current rating to both the charger and the laptop. Without it, devices default to 3A (60W) for safety, even if you’re using a charger rated for 100W.

For PD 3.1 (240W), you must use an EPR-certified cable. Standard 5A cables cannot handle the higher voltages and will fail dangerously. EPR cables use a split-rail design inside the connector to safely carry 48V at 5A.

Practical recommendation: If you’re buying a new USB-C charger, buy a quality cable with it (or separately). Reputable brands like Anker, Belkin, and Nekteck include emark chips in all their cables. Avoid ultra-cheap Amazon knockoffs.

Which Laptops Support Which USB-C PD Version?

Most modern laptops (post-2016) support at least USB-C PD 2.0 or higher. Here’s a rough breakdown by device class:

A universal rule: Any laptop made after 2018 with USB-C will work with a 65W or 100W USB-C PD charger. The negotiation is smart enough to fall back to lower wattages if the charger doesn’t advertise higher ones.

The exception is gaming laptops and 16″ MacBook Pros, which benefit from 140W+ charging to reduce charge time. A 65W charger will still work, but the laptop may charge at half-speed while gaming.

Recommended USB-C PD Chargers by Wattage

The charger you choose should match your laptop’s maximum supported wattage. Here are the most common options:

45W Chargers — Ultra-slim ultrabooks

Best for: MacBook Air 13″, Dell XPS 13, lightweight ultrabooks under 1.2kg.

A 45W charger is the smallest and most portable USB-C charger option. It’s perfect if your laptop is consistently under 15W continuous power draw (most business ultrabooks).

Browse 45W USB-C PD Chargers on Amazon UK

65W Chargers — The sweet spot

Best for: Dell XPS 15, MacBook Pro 14″, Lenovo ThinkPad X1, most 15″ business laptops.

A 65W charger handles almost all non-gaming laptops. It’s the most common wattage on the market and offers the best balance of power and portability. If you’re buying one charger for multiple devices, buy 65W.

Browse 65W USB-C PD Chargers on Amazon UK

100W Chargers — Gaming and high-power laptops

Best for: MacBook Pro 16″, ASUS ROG gaming laptops, workstations, future-proofing.

A 100W charger is essential if you game or run GPU-intensive work on a larger laptop. It supports the full PD 2.0 spec and is compatible with virtually all modern laptops. If you’re unsure, buy 100W — it won’t hurt, and you’re future-proof.

Browse 100W USB-C PD Chargers on Amazon UK

140W+ Chargers — Gaming-specific

Best for: High-end ASUS ROG, Alienware, MSI gaming laptops (2021+).

140W chargers support PD 3.1 Extended Power Range and are designed for dedicated gaming laptops that draw sustained power above 100W. They’re larger and less portable than 65–100W options. Only buy this if your laptop’s specifications explicitly call for it.

Browse 140W+ USB-C PD Chargers on Amazon UK

FAQ: USB-C Power Delivery

Can I use a 100W charger on a 65W laptop?

Yes, absolutely. The laptop negotiates down to the highest wattage it needs. A 100W charger will safely deliver 65W to a 65W laptop. The only downside is that the charger is larger and more expensive than necessary — there’s no risk to the laptop.

Can I use a 45W charger on a 65W laptop?

Yes, but the laptop will charge slower. Your laptop will charge at 45W instead of 65W, which means it might take 50% longer to fully charge. This is safe — the laptop won’t overheat or be damaged — but it’s inconvenient. Avoid 45W chargers for 65W+ laptops.

What does “PPS” mean? Do I need it?

PPS stands for Programmable Power Supply. It allows chargers to fine-tune voltage continuously rather than in fixed steps. It’s beneficial for phones but makes minimal difference for laptops. You don’t need to specifically buy a PPS charger for laptop use, but if one is available at the same price, it’s a nice-to-have.

Why does my USB-C charger only deliver 45W when it says 100W?

Most likely, you’re using a USB-C cable without an emark chip. The cable is limiting the negotiation to 3A (60W at 20V). Buy a 5A emark-certified cable and the charger will deliver its full power. You can verify this by checking if there’s a small emark logo on the cable connector.

Are all USB-C chargers compatible with all USB-C laptops?

Almost always, yes — but with rare exceptions. Very old laptops (2015–2016 with early USB-C implementations) sometimes have compatibility quirks. Modern laptops (2017+) have PD negotiation baked into the USB-C controller and are universally compatible. When in doubt, check the laptop manufacturer’s specifications for recommended charger specs.

Is a higher wattage charger always better?

Not necessarily. A 100W charger is overkill for a 45W ultrabook and will cost more, use more energy, and be heavier to carry. Match the charger’s wattage to your laptop’s actual power draw. That said, if you own multiple devices or want a single charger for several years, 65–100W is the safest choice.

Recommended Products

These are the products we recommend based on this guide. All links go to Amazon UK where you can check current prices and availability.

Prices and availability may vary. As an Amazon Associate, we earn from qualifying purchases.

Related Guides

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• Lenovo Laptop Charger Compatibility
• Best Usb C Charger Lenovo Thinkpad
• Best Macbook Charger

Related guides:

• Laptop Charger Compatibility Guide
• USB-C Cable Types Explained