Safety Guidelines
Read this chapter before connecting the hardware to any circuit.
The Active-Pro Firmware Debugger is used to connect to and monitor electronic signals from your own hardware designs. The following section is intended to help you understand what types of signals it can safely connect to, and which signals will damage the device.
No Galvanic Isolation
WARNING: The Active-Pro is NOT galvanically isolated when connected via USB.
This mainly concerns systems where the target circuit AND the PC are plugged into AC power outlets. If your target system OR the PC (laptop) are battery powered, there is no issue. If your PC and target circuit have different ground reference levels, connecting them together using the Active-Pro GND signal can damage the devices.
The USB ground is electrically connected to the test lead ground. There is no transformer or optocoupler between the PC and your target.
To ensure both your PC and target system share the same ground reference:
Use polarized power cords for both the PC and target and plug them into the same AC circuit. If you use non-polarized power cords or use separate power circuits, the PC and target system may have different ground references, which can damage the Active-Pro, target, and/or PC.
Ensure that a GND signal on the Active-Pro is connected to the target ground (and not to any other voltage level).
If your target is floating (battery-powered or isolated), this is not a concern — the Active-Pro will establish the reference when you connect the ground lead.
Input Voltage Limits
Do not exceed the input voltage ratings of the hardware you are using. Exceeding these limits will permanently damage the device.
| Model | Digital inputs (D0–D7) | Analog inputs |
|---|---|---|
| Active Debugger | −20 V to +20 V | N/A |
| ACTIVE-PRO | −0.5 V to +6 V (sustained); −30 V to +30 V (transient) | −30 V to +30 V |
| ACTIVE-PRO Ultra | −25 V to +25 V (transient tolerance) | −30 V to +30 V |
The ACTIVE-PRO digital inputs are limited to −0.5 V to +6 V for continuous signal levels. The transient protection handles brief spikes up to ±30 V but is not designed for sustained over-voltage. If your signal levels exceed 5 V, the Active Debugger or ACTIVE-PRO Ultra (which accepts ±25 V on digital inputs) is the appropriate choice.
As with all electronic equipment where you are working with live voltages, it is possible to hurt yourself or damage equipment if not used properly. Although we have designed the Active-Pro pod for normal operating conditions, you can cause serious harm to humans and equipment by using the pod in conditions for which it is not specified.
Output Lead Precautions
Available on: ACTIVE-PRO · ACTIVE-PRO Ultra
The Active-Pro actively drives pod signals A0, A1, D0, and D1. Do not connect these leads to signals that are already being driven by another source. Two driven signals fighting each other can damage the active-pro hardware and the target circuit. Before enabling an output pin, confirm the target net is either undriven (floating) or resistively driven (pull-up or pull-down only).
Connection Order
Follow this order when setting up:
- Plug the Active-Pro pod into a powered PC via USB first.
- Connect the ground lead to your target circuit's ground.
- Connect the remaining signal leads.
When disconnecting:
- Disconnect all signal leads from your target.
- Disconnect the ground lead.
- Unplug the USB cable if desired.
Unplug the Active-Pro from your design BEFORE powering off or unplugging the USB cable.
Working Near Live Voltages
- The active-pro is designed for low-voltage electronics work (logic levels and low-voltage analog signals).
- Do not use it to probe mains voltage (120 VAC / 240 VAC) or any signal referenced to mains potential.
- Keep probe leads organized to avoid accidental shorts on dense PCBs.
- Small clips on fine-pitch components require care — a slipped clip can short adjacent pins.
USB-C Cable Requirement
Use a USB-C cable rated for the connection speed of your device:
- Active Debugger and ACTIVE-PRO: any USB-C cable works (Full-Speed and High-Speed respectively)
- ACTIVE-PRO Ultra: use a USB 3.x SuperSpeed-rated USB-C cable and port for full bandwidth
A USB 2.0 cable connected to the Ultra will limit transfer bandwidth. The application will warn you when this condition is detected.
Quick Safety Checklist
- ALWAYS connect at least one GND line to your circuit's ground before connecting any signal leads
- NEVER connect digital input signal lines to any voltage outside the specified range for your model
- NEVER connect analog input lines to any voltage outside −30 V to +30 V
- The Active-Pro actively drives A0, A1, D0, and D1 — make sure these leads are either unconnected or not also being driven by another source
- Plug in the Active-Pro pod into a powered PC BEFORE connecting leads to your design
- Unplug the Active-Pro from your design BEFORE powering off or unplugging the USB cable