## Common ground
All options are printed circuit board assemblies (PCBAs) used in specific electronic devices or systems.
## Options at a glance
**8473.30 – Designed for computers**
- **Defining trait:** Primarily used in computers or computer units.
- **Typical examples:** Motherboard, GPU card, CPU cooling control board.
- **Best fit when:** The PCB is part of a general-purpose computing device.
**8504.90 – For transformers and power converters**
- **Defining trait:** Used in electrical power conversion devices like transformers or static converters.
- **Typical examples:** Inverter control board, switch-mode power supply (SMPS) controller.
- **Best fit when:** The PCB manages high-power AC/DC conversion or voltage regulation.
**8517.62 – For wireless headsets**
- **Defining trait:** Specifically for wireless audio/data transmission between headset and panel.
- **Typical examples:** Bluetooth headset control board, wireless earbud signal processor.
- **Best fit when:** The PCB enables wireless communication in audio devices.
**8529.90 – For televisions**
- **Defining trait:** Used in television sets as part of their core display or signal processing system.
- **Typical examples:** TV mainboard, HDMI interface board.
- **Best fit when:** The PCB is integral to a TV’s video/audio processing.
**8531.90 – For sound or visual signaling devices**
- **Defining trait:** Part of systems that emit audible or visible alerts (e.g., alarms).
- **Typical examples:** Fire alarm control board, traffic light controller.
- **Best fit when:** The device is used for safety or warning signals.
**8537.10 – With switches, connectors, thermostat, etc.**
- **Defining trait:** Contains a mix of mechanical and electrical components (e.g., switches, thermostats).
- **Typical examples:** HVAC control board, appliance interface panel.
- **Best fit when:** The PCB integrates user controls and sensors in a device.
**8538.90 – For apparatus in 85.35–85.37**
- **Defining trait:** Designed for use with equipment classified under headings 85.35 to 85.37 (e.g., measuring instruments, control systems).
- **Typical examples:** Industrial sensor controller, process automation board.
- **Best fit when:** The PCB is part of a specialized electronic instrument or control system.
**8543.90 – For capacitive touch keypads**
- **Defining trait:** Specifically designed for capacitive touch input interfaces.
- **Typical examples:** Touch panel controller, smart switch interface.
- **Best fit when:** The PCB enables touch-based user input.
**9019.20 – For medical respiratory therapy devices**
- **Defining trait:** Used in medical equipment for oxygen, ozone, or artificial respiration.
- **Typical examples:** Oxygen concentrator control board, ventilator interface.
- **Best fit when:** The PCB is part of a life-support or therapeutic medical device.
**9405.92 – For lamps**
- **Defining trait:** Used in lighting fixtures (e.g., LED drivers, dimmers).
- **Typical examples:** Smart lamp controller, LED driver board.
- **Best fit when:** The PCB controls a light source or lighting system.
## Key differences
| HS Code | Primary Function | Key Component Type | Main Application Type |
|--------|------------------|--------------------|------------------------|
| 8473.30 | Computing | CPU, memory | Computers |
| 8504.90 | Power conversion | High-power components | Power systems |
| 8517.62 | Wireless audio | RF modules | Headsets |
| 8529.90 | Video/audio processing | Display drivers | TVs |
| 8531.90 | Signaling | Alarms, LEDs | Safety devices |
| 8537.10 | Control integration | Switches, thermostats | Appliances |
| 8538.90 | Instrument control | Sensors, logic | Industrial systems |
| 8543.90 | Touch input | Capacitive sensors | Keypads |
| 9019.20 | Medical therapy | Life-support controls | Medical devices |
| 9405.92 | Lighting control | LED drivers | Lamps |
## How to choose
- Is it used in a computer? → 8473.30
- Does it manage power conversion (e.g., AC/DC)? → 8504.90
- Is it for wireless audio transmission (e.g., Bluetooth headset)? → 8517.62
- Is it part of a television? → 8529.90
- Does it trigger alarms or signals? → 8531.90
- Does it include switches, thermostats, or user controls? → 8537.10
- Is it for industrial instruments (e.g., sensors, automation)? → 8538.90
- Is it for touch input (e.g., capacitive keypad)? → 8543.90
- Is it used in medical respiratory therapy? → 9019.20
- Is it part of a lamp or lighting system? → 9405.92
## Overlaps & pitfalls
- A PCB for a smart lamp with touch control could fit both **8543.90** and **9405.92**.
- A medical ventilator board may overlap **9019.20** and **8538.90**.
- If multiple functions apply, prioritize the **main purpose**: e.g., if it’s a medical device, use 9019.20 even if it has touch or control features