Dual USB Charger Design - Powering dual ports - Page 1
Forum section: electronics / beginners

author: Freshman
author_rank: Regular Contributor
timestamp: June 06, 2025, 01:16:07 pm
content: Working on a dual mobile charging socket design having Type-A (5V and 3A) and Type-C (15W, 27W, 45W & 68W).USB Type-A: 5V @ 3AUSB Type-C:5V @ 3A9V @ 3A15V @ 3A20V @ 3.4A (PD support)So, the idea I got is to design the power path for both the ports independently, similar to the Figure 2-2 on page 5 of this device (https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP22301-Stand-Alone-USB-Type-C-Power-Delivery-3-dot-1-Controller-DS20006887.pdf). This device appears to be fit my requirement for Type-C channel. So, I am planning to use this device for the Type-C port.I need advice on how do I power or design the channel path for the Type-A port.From what I see, I think that we cannot provide 3A from a USB Type-A connector at 5V, correct?I mean, there's no USB standard definition. However, it seems some proprietary solution is there that can provide 5V and 3A from USB Type-A, correct? I read that QualComm's quickcharge provides 5V & 3A?Any design advice/solution on how to achieve this (5V and 3A) without using proprietary solutions?I am planning to use this regulator (https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP19061-Synchronous-Four-Switch-Buck-Boost-Analog-Front-End-DS20006888.pdf) to provide the power to both the USB Channels for the mentioned power requirements.Looking for some solution advice for both the ports. Some block diagram might help me.

author: mariush
author_rank: Super Contributor
timestamp: June 06, 2025, 01:41:16 pm
content: You don't "provide" 3A on 5v , you just make your dc-dc converter capable of providing that much current. How much the device pulls depends on its internal circuitry... but will most likely limit themselves to taking only 1A or 2A unless you put some resistors on the data pins or unless you use a chip to "talk" to the device that wants to take power.To give you an example of such chips, here's a basic one , Injoinic IP6525T :https://www.lcsc.com/product-detail/USB-PD_INJOINIC-IP6525T_N_C515678.html?s_z=n_INJOINICIt's basically a dc-dc buck (step-down) regulator that you power with at least 10v (12v or more recommended, up to 32v) and it can communicate with the device through the USB data wires and automatically reduces the voltage to 5v, 9v or 12v with a 18w limit 5V@3.4A，9V@2A, 12v @ 1.5A )So this one is pretty much only for Type A because it doesn't connect to the DPC / DMC / CC1 / CC2 pins of USB Type CThen you have slightly more complex chips like IP2701 which can also use the pins of USB Type C :https://www.lcsc.com/product-detail/USB-PD_INJOINIC-IP2709_BF20WP_C20606460.html?s_z=n_INJOINICThis only negotiates the voltage and current (up to 12v for this chip), you need a separate dc-dc converter to produce the voltage the chip negotiates with the device that takes power at the other end of the cable.

author: Freshman
author_rank: Regular Contributor
timestamp: June 06, 2025, 03:54:49 pm
content: Thanks @mariush, it helped me.So, the underlying concept of negotiation of current and voltage levels between the device and the host , happens only on D+ and D- lines in case of Type-A (even if the USB connector is a blue connector which has 9 pins and supports USB 3.0, no role is played by the USB SuperSpeed lines, and only the D+and D- lines, right?), right?And the power negotiation in Type-C connectors happens only due through the CC pins, correct? In Type-C, the D+ and D- lines and the SuperSpeed lines, play no role, right?