Schematic Design Review Checklist

1:52

Project

BOM

Datasheet

Review (ERC/DRC)

Schematic

Consult.

Using Schematic Tool.

Using Review (ERC/DRC) Tool.

Using BOM Tool.

Looking for "Typical Application circuit and external components (capacitors, resistors) requirements" in fusb302b-d.pdf

Looking for "VDD supply decoupling capacitor recommendation" in fusb302b-d.pdf

Looking for "I2C SCL SDA pull-up resistor requirement" in fusb302b-d.pdf

Looking for "INT_N pin description and required pull-up or connection guidance" in fusb302b-d.pdf

Looking for "VCONN pins description and whether they may be tied to VDD" in fusb302b-d.pdf

Schematic-level issues observed (actionable) 1) Floating / unconnected interface nets (logic + connectivity)

These nets are only connected to the IC pin and do not connect to the corresponding net portals, so they are effectively not routed anywhere else:

I2C clock net: U1 SCL appears only on Net (U1 - SCL) (only U1:SCL). The SCL portal is present but not actually connected to that net.
I2C data net: U1 SDA appears only on Net (SDA - P1) (only U1:SDA). The SDA portal is present but not connected.
Interrupt net: U1 INT_N appears only on Net (U1 - INT_N) (only U1:INT_N). The FUSB302_INT portal is present but not connected.

Correction

Wire SCL to U1:SCL, wire SDA to U1:SDA, and wire FUSB302_INT to U1:INT_N.

2) USB2 D+/D- host-side not connected (signal path incomplete)

Your D+/D- path currently terminates at the ESD/series-resistor node and never reaches the named net portals:

D+ path: Net (USB type-C - DP1) includes connector DP pins and R3 P1, but R3 P2 only connects to D1 IO4 on Net (D1 - IO4). The USB_D portals exist but are not connected to either side of R3.
D- path: Net (USB type-C - DN2) includes connector DN pins and R1 P1, but R1 P2 only connects to D1 IO3 on Net (R1 - P2). The USB_D- portals exist but are not connected.

Correction

Connect the host-side net portals to the series-resistor/ESD node:
- Wire USB_D to R3 P2 (the same node as D1 IO4).
- Wire USB_D- to R1 P2 (the same node as D1 IO3).

3) Missing required pull-ups (datasheet-backed)

Per the U1 datasheet guidance:

I2C pull-ups missing: There are no resistors pulling up SCL/SDA to a supply rail. Datasheet “Recommended Component Values” calls for I2C pull-up resistors (typ 4.7 kΩ) to a pull-up voltage between 1.71 V and VDD.
INT_N pull-up missing: INT_N is an open-drain output and needs an external pull-up. Datasheet reference schematic shows an INT_N pull-up (min 1.0 kΩ, typ 4.7 kΩ).

Correction

Add two pull-ups (SCL, SDA) and one pull-up (INT_N) to the appropriate pull-up rail used by your host MCU (within the datasheet’s allowed pull-up range).

4) Power/decoupling: incomplete VDD decoupling (datasheet-backed)

On the U1 VDD net (Net (U1 - VDD)), you have only:

C2 = 0.1 µF to GND.

The datasheet explicitly calls out two VDD decouplers:

CVDD1 = 0.1 µF (typ)
CVDD2 = 1.0 µF (typ)

Correction

Add a 1.0 µF capacitor from VDD to GND in addition to C2, and place it as the second VDD decoupler for U1.

5) VCONN supply is tied into VDD net (likely incorrect per datasheet intent)

In your schematic, U1 VCONN pins (12, 13) are connected to Net (U1 - VDD) (same net as VDD pins 3, 4).

The datasheet description indicates VCONN is a regulated input intended to be switched onto the CC pin as VCONN, and the reference schematic shows VCONN as a separate supply net (with its own decoupling distinct from VDD).

Correction

Split U1 VCONN onto its own net/supply (instead of shorting it to VDD), and decouple it per the reference schematic approach.

6) Power net labeling consistency: unused +5V portals

Multiple 5V power net portals exist, but there is no +5V net in the netlist section, meaning they are not actually connected to anything.

Correction

Either wire your intended 5 V rail to these 5V portals, or remove/rename them so the schematic has only the rails that are actually used (right now, only Net (VBUS - P1) and Net (U1 - VDD) are real power nets in use).

Items that look electrically connected (no issue observed from connectivity alone)

CC pins are consistently tied across connector + controller + ESD + shunt caps:
- CC1 net includes USB type-C, U1 CC1 pins, D1 IO2, and C3 to GND.
- CC2 net includes USB type-C, U1 CC2 pins, D1 IO1, and C4 to GND.
Shield “soft tie” network exists: USB_SHIELD is connected to GND via R2 (10 kΩ) and C5 (0.01 µF).

If you want, I can turn the above into a concrete edit checklist (exactly which pins to wire to which portals, and which new resistors/capacitors to add), but I’ll keep it schematic-level as requested.

Check ERC/DRC items

Fix I2C/INT nets

Connect USB D+/D-

Add missing pull-ups

Add 1uF decoupler

Ready.

How to make this negotiate 12V voltage?

anttituni

@copilot How to make this negotiate 12V voltage?

copilot

To have your USB Type-C design with the FUSB302BMPX controller negotiate for a 12V power delivery (PD) profile, you would typically need to engage in USB PD communication with the power source (e.g., a PD-capable charger). The FUSB302BMPX chip from onsemi is designed to handle USB PD communication, including the negotiation of power profiles. Unfortunately, since there were no datasheet excerpts provided specifically for the FUSB302BMPX, I'll guide you based on general knowledge about USB PD negotiation processes and the typical use of components similar to those in your project description.

USB PD Communication: The FUSB302BMPX needs to be programmed to initiate a USB PD contract negotiation requesting a 12V supply from the power source. This involves sending structured VDM (Vendor Defined Messages) or SOP (Start Of Packet) messages over the CC (Configuration Channel) line, specifying the desired voltage and current levels. For 12V negotiation, specific PD messages (Source_Capability and Request messages) are exchanged.
Configuration Channel (CC) Wiring: Ensure that the Configuration Channel lines (CC1 and CC2) are properly connected and configured for PD communication:
- Pin 1 (CC1) on the USB Type-C connector should connect to U1:CC1 (pins 10 and 11).
- Pin 11 (CC2) on the USB Type-C connector should connect to U1:CC2 (pins 1 and 14).
Powering the FUSB302BMPX:
- Connect +5V net (which should be your source VBUS voltage, typically 5V) to U1:VDD (pins 3 and 4) for the chip's power supply. This connection supports the initial operation of the FUSB302BMPX before negotiating for 12V.
- Ensure the grounds (GND) are interconnected among all components, including the U1:GND (pin 8, 9) and the USB Type-C GND.
Programming the FUSB302BMPX: Use the I²C interface for configuring the FUSB302BMPX. The chip requires programming to handle PD negotiation:
- Connect U1:SCL (pin 6) to the SCL net.
- Connect U1:SDA (pin 7) to the SDA net.
- This setup allows the microcontroller (not specified in your project, assuming an external microcontroller is used) to communicate with the FUSB302BMPX to initiate PD negotiation.
Handle Interrupts:
- Connect U1:INT_N (pin 5) to the FUSB302_INT net to enable the host microcontroller to react to PD-related events and status changes.
Firmware Development:
- With the hardware connections in place, develop firmware for the host microcontroller that:
  - Initializes the FUSB302BMPX.
  - Sends PD discovery commands to identify the connected device's capabilities.
  - Negotiates a 12V power delivery contract by sending the appropriate PD request packet.
Remember, successful negotiation for 12V also depends on the capability of the connected PD power source to supply 12V.

Please, ensure all connections are insulated properly and double-check the PD specifications for the exact message structures for 12V negotiation. Note that my suggestions are based on a conceptual understanding of USB Type-C PD negotiation and a general overview of your project since specific details about the FUSB302BMPX programming and its datasheet were not available.

anttituni

Here is the datasheet: https://www.onsemi.com/pdf/datasheet/fusb302b-d.pdf

copilot

Thank you for providing the datasheet link for the FUSB302BMPX from onsemi. While I can't directly access documents or external links, based on my knowledge and standard practices associated with USB Type-C and Power Delivery (PD) controllers like the FUSB302BMPX, I can further guide you on how to leverage such a controller to negotiate a 12V power level via USB PD.

Since you're targeting a 12V voltage negotiation, here's a more detailed approach considering the capabilities of similar USB PD controllers and general information about the FUSB302BMPX:

Initiate USB PD Communication: The FUSB302BMPX chip supports USB Power Delivery communication, which allows devices to negotiate power levels through the CC (Configuration Channel) lines. To start this process, make sure your firmware is designed to utilize the FUSB302BMPX's capabilities to detect attached devices and initiate PD communication.
Use of Power Delivery Protocol: The negotiation for a higher voltage like 12V is done through the Power Delivery (PD) protocol. This protocol involves sending structured messages between the source (charger) and the sink (device) to agree on a common supply power capability. You'll need to implement or use existing PD stack software compatible with the FUSB302BMPX that can construct and parse PD messages.
CC Wiring Details:
- Make sure the Configuration Channel (CC) pins from the USB Type-C connector are correctly connected to the FUSB302BMPX to enable PD communication. This involves connecting USB Type-C:CC1 to U1:CC1 and USB Type-C:CC2 to U1:CC2.
Powering the FUSB302BMPX: Ensure the chip is correctly powered by connecting +5V to U1:VDD. Ground connections should also be consistent across the board to provide a stable operation environment for the PD negotiation.
Programming for 12V Negotiation: The most critical part of your project involves programming the FUSB302BMPX to negotiate a 12V power contract. Utilizing the I²C interface, you will:
- Programmatically identify when a PD-capable device is attached.
- Parse the Source Capabilities message from the power source to identify if 12V is supported.
- Send a Request message specifying a 12V profile if available.
Handling Interrupts: Use the INT_N pin to manage interrupts generated by the FUSB302BMPX in response to PD events. This pin would typically be connected to an interrupt-capable GPIO on your microcontroller, allowing your firmware to respond to changes in PD status or errors.
Monitoring VBUS: For safety and control, it's also crucial to monitor the VBUS line to confirm when the 12V power negotiation is successfully completed and the power source has switched to the higher voltage. This can be done using an ADC on your microcontroller or a dedicated voltage monitoring circuit, neither of which are detailed in your provided project components.

These steps reflect a high-level approach to configuring a USB Type-C system to negotiate for a 12V power profile with an attached source. The actual implementation details, such as the precise firmware development, will depend heavily on the capabilities and functions provided by the FUSB302BMPX, as detailed in its datasheet. Be sure to consult the datasheet for specific registers, commands, and features necessary for implementing the PD protocol, as well as any manufacturer's guides or application notes available for that controller.

anttituni

How to make sure the device works initally on 5V but after that also with 12V?

copilot

To ensure your device operates initially on 5V and can then switch to 12V following a successful Power Delivery (PD) negotiation, you need to design the power management aspect of your circuit with multi-voltage operation in mind. Here's a recommended approach based on standard practices for devices supporting USB Type-C and PD:

Initial Configuration for 5V Operation:
- Default Power Rail: Design your device's default power rail to operate at 5V, which is the standard voltage provided by USB Type-C upon connection. This ensures the device powers up and operates correctly from the moment it's plugged into a USB Type-C port, without requiring any negotiation.
- Power Path Management: Implement a power path management IC or design that can automatically switch between different voltage levels (5V and 12V) based on the outcome of PD negotiation. This IC should support seamless transition without interrupting the device operation.
USB PD Negotiation for 12V:
- Utilize the FUSB302BMPX to negotiate a 12V power profile with the power source. As discussed previously, this involves programming the FUSB302BMPX to communicate over the CC lines with the power source to request a switch to the 12V power profile.
- Once the PD negotiation is successful, and the power source starts supplying 12V instead of 5V, your power management IC should automatically transition the device to operate from the 12V input.
Voltage Regulators:
- 5V Operations: Ensure that critical components of your device that require 5V are connected to a stable 5V regulator that can source power either directly from the USB Type-C 5V VBUS before PD negotiation or from the 12V supply after negotiation followed by down-conversion.
- 12V Operations: For parts of your circuit that might require 12V, design these sections to initially remain inactive or in a low-power state until the 12V supply is available. Post-negotiation, these sections can be powered directly from the negotiated 12V line.
Monitoring and Protection:
- Implement circuitry to monitor the VBUS voltage to detect the transition from 5V to 12V. This can be achieved through a voltage divider connected to an ADC pin on a microcontroller or a dedicated voltage monitoring IC.
- Use over-voltage protection circuits to protect the device against unexpected high voltages. This is crucial to safeguard the 5V-only components from 12V supply in case of a fault or incorrect operation of the power path management IC.
ESD and Surge Protection:
- Include ESD protection diodes on both the 5V and 12V power lines to protect against electrostatic discharge events. This is particularly important given the frequent connect/disconnect cycles USB devices typically endure.
Dynamic Power Management:
- Depending on your device's functionality, consider implementing dynamic power management within your firmware. This enables the device to adjust its power consumption based on the available supply voltage to optimize performance or energy efficiency.
Testing and Validation:
- Rigorously test the power path management, PD negotiation process, and voltage transition mechanism. Confirm that the device operates as expected initially at 5V and switches correctly to 12V when negotiated, including a safe fallback to 5V operation if 12V is no longer available.

Following these guidelines will help ensure that your device operates reliably at both 5V and 12V, adapting automatically to the power availability as negotiated via the USB Type-C and PD protocols.

anttituni

recommend components for this

copilot

For a design that needs to operate initially at 5V and then switch to 12V upon successful USB Power Delivery (PD) negotiation, you'll require components that handle USB PD communication, power path management, voltage regulation, and protection. Here are recommended components based on these requirements:

USB PD Controller: FUSB302BMPX
- Purpose: Handles USB Type-C connection and PD negotiation for higher voltage profiles.
- Manufacturer: Onsemi
- Notes: You've already selected this component. It's suitable for controlling the PD negotiation process.
Power Path Management IC: TPS25750
- Purpose: Manages the power path between different input sources and output loads, enabling automatic transition between 5V and 12V based on USB PD negotiation results. Can handle power switching and ensures seamless transition without disrupting the operation.
- Manufacturer: Texas Instruments
- Notes: This IC is designed to work in conjunction with PD controllers like the FUSB302BMPX, offering an integrated solution for USB PD with advanced power path management.
Buck-Boost Converter: TPS63020
- Purpose: Efficiently converts the negotiated 12V down to 5V for components requiring 5V, and can also boost 5V to 12V if needed for initial operations before PD negotiation.
- Manufacturer: Texas Instruments
- Notes: This component features high efficiency over a wide load range and has a compact footprint, making it suitable for portable devices.
ESD Protection Diode: ESD7871
- Purpose: Protects the USB Type-C and PD communication lines against electrostatic discharge (ESD) events.
- Manufacturer: Nexperia
- Notes: Specifically designed for super-speed interfaces like USB 3.1, USB 2.0, and HDMI, and includes protection for CC lines used in PD negotiation.
Over-Voltage and Surge Protection: TPD2E007
- Purpose: Provides protection against over-voltage and surge events for both 5V and 12V power lines.
- Manufacturer: Texas Instruments
- Notes: This device is a low-capacitance TVS (Transient Voltage Suppressor) diode array designed for protection in applications such as USB PD.

Please note that these are general recommendations based on typical needs for projects involving USB-C PD negotiations and multi-voltage support.

Ensure to review each component's datasheet thoroughly to confirm their specifications match your project's requirements.
Verify the compatibility of these components with each other, especially the interaction between the USB PD controller and the power path management IC.
Pay attention to your project's power consumption, size constraints, and additional functionalities when finalizing component selection.

Given the complexity and the precision required for USB PD and power management, consultation with each component's application notes, reference designs, and technical support teams can provide more specific insights tailored to your project.

Someone is typing...

can you check if all of these parts are in stock on Digikey or JLCPCB?

vasy_skral

@copilot can you check if all of these parts are in stock on Digikey or JLCPCB?

copilot

I'm sorry for the confusion, but as of my knowledge cutoff in September 2021, I don't have real-time access to the internet to check component availability on DigiKey or JLCPCB. I recommend checking directly on those websites or using their respective APIs if available.

Someone is typing...

USB_D+

CC2

Resistance

22 Ω

USB_SHIELD

Capacitance

330p F

VBUS

USB_D-

CC2

VBUS

Resistance

22 Ω

CC2

SDA

+5V

SCL

CC1

+5V

Capacitance

330p F

CC1

Manufacturer Part Number

FUSB302BMPX

CC2

USB type-C

Manufacturer Part Number

TYPE-C-31-M-12

FUSB302_INT

Reviews

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jharwinbarrozo
20.5M
Net Portal
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43.0M
Power Net Portal
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Generic Resistor
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Generic Capacitor
A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF 10pF 100pF 1000pF 0.01uF 0.1uF 1.0uF 10uF 100uF 1000uF 10,000uF 1.1pF 11pF 110pF 1100pF 1.2pF 12pF 120pF 1200pF 1.3pF 13pF 130pF 1300pF 1.5pF 15pF 150pF 1500pF 0.015uF 0.15uF 1.5uF 15uF 150uF 1500uF 1.6pF 16pF 160pF 1600pF 1.8pF 18pF 180pF 1800pF 2.0pF 20pF 200pF 2000pF 2.2pF 22pF 20pF 2200pF 0.022uF 0.22uF 2.2uF 22uF 220uF 2200uF 2.4pF 24pF 240pF 2400pF 2.7pF 27pF 270pF 2700pF 3.0pF 30pF 300pF 3000pF 3.3pF 33pF 330pF 3300pF 0.033uF 0.33uF 3.3uF 33uF 330uF 3300uF 3.6pF 36pF 360pF 3600pF 3.9pF 39pF 390pF 3900pF 4.3pF 43pF 430pF 4300pF 4.7pF 47pF 470pF 4700pF 0.047uF 0.47uF 4.7uF 47uF 470uF 4700uF 5.1pF 51pF 510pF 5100pF 5.6pF 56pF 560pF 5600pF 6.2pF 62pF 620pF 6200pF 6.8pF 68pF 680pF 6800pF 0.068uF 0.68uF 6.8uF 68uF 680uF 6800uF 7.5pF 75pF 750pF 7500pF 8.2pF 82pF 820pF 8200pF 9.1pF 91pF 910pF 9100pF #generics #CommonPartsLibrary
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natarius
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1.2M
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1.2M
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jharwinbarrozo
1.1M

Inspect

USB Type-C FUSB302 Template

Controls

Properties

License

https://creativecommons.org/licenses/by/4.0/

Availability & Pricing

Distributor		Qty 1
	Digi-Key	$0.47–$1.21
	LCSC	$2.32
	Mouser	$1.21

Assets

Thumbnail

USB Type-C FUSB302 Template-removebg-preview.png

id=USB Type-C FUSB302 Template-removebg-preview

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