Converter Circuit Board
The Converter Circuit Board converts the frequency pulse output of the FG-3+ or FG-4 sensor into a proportional analog voltage. This allows fluxgate sensors to be connected directly to analog data acquisition systems, PLCs, oscilloscopes, or any ADC input — without requiring a microcontroller with frequency counting capability.
When to Use the Converter Circuit Board
| Scenario | Use Converter Board? |
|---|---|
| Connecting to an oscilloscope | ✅ Yes |
| Connecting to a PLC analog input | ✅ Yes |
| Connecting to a DAQ (NI, Measurement Computing, etc.) | ✅ Yes |
| Connecting to a legacy analog data recorder | ✅ Yes |
| Connecting to an Arduino or ESP32 with timer input | ❌ Not required |
| Using with MAG-BOARD or FGA Logger | ❌ Not required |
Signal Chain
FG-3+ / FG-4 ──► Converter Circuit Board ──► ADC / DAQ / PLC / Oscilloscope
(frequency) (frequency → voltage) (analog input)
The Converter Circuit Board accepts the raw pulse output from the sensor and outputs a voltage that is proportional to the measured magnetic field.
Electrical Interface
| Signal | Description |
|---|---|
| Sensor input | 5 V pulse signal from FG-3+ or FG-4 |
| Analog output | Voltage proportional to magnetic field |
| Supply | 5 V regulated |
| GND | Common ground |
The exact analog output voltage range and scaling factor (V/nT or V/µT) are not documented publicly. Contact FG Sensors or refer to your supplied calibration sheet for the transfer function of your specific unit.
PCB Size
The Converter Circuit Board is a compact PCB designed for easy integration into instrument housings and custom enclosures.
Exact PCB dimensions are not documented publicly. Contact FG Sensors for mechanical drawings if required for enclosure design.
Integration Notes
- The analog output is a low-impedance signal suitable for driving standard ADC inputs
- Use shielded cable between the Converter Board output and the ADC to minimize noise pickup
- Mount the board as close to the sensor as practical to keep the high-frequency pulse line short
- Ensure the Converter Board and the ADC share a common GND reference to avoid ground loop errors
Do not connect the Converter Board output directly to an input rated below its output voltage swing. Check the output range against your ADC or PLC input specification before connecting.