ADF4351 Controller

Arduino controller programs for the ADF4351 PLL frequency synthesizer with comprehensive register library following the ADF4351 datasheet. Includes manual control and automated sweep functionality.

Repository Structure

This repository is structured as an Arduino library following the official Arduino library specification.

adf4351-controller/
├── README.md                  # This file
├── LICENSE                    # MIT License
├── library.properties         # Arduino library metadata
├── src/                       # Library source code
│   ├── ADF4351Controller.cpp  # ADF4351 register implementation
│   └── ADF4351Controller.h    # ADF4351 register header
└── examples/                  # Example sketches
    ├── ManualControl/         # Interactive serial control
    │   └── ManualControl.ino
    ├── BasicSweep/            # Configurable GPIO-controlled sweep
    │   └── BasicSweep.ino
    ├── SweepMixer/            # Band A sweep for mixer measurements
    │   └── SweepMixer.ino
    └── SweepFilter/           # Band B dual-power sweep for filter characterization
        └── SweepFilter.ino

Examples

1. ManualControl

File: examples/ManualControl/ManualControl.ino

Interactive serial control program for manual frequency setting and testing.

Features:

Manual frequency input via serial interface
Real-time frequency adjustment
Output power control (-4, -1, +2, +5 dBm)
Lock detect monitoring
Register calculation using ADF4351 datasheet specifications

Usage:

Upload to Arduino
Connect via USB
Open Serial Monitor (115200 baud)
Use commands to control the ADF4351

Serial Commands:

f <MHz> - Set specific frequency (e.g., f 742.4)
p <dBm> - Set output power: -4, -1, +2, or +5 dBm (e.g., p 5)
n - Advance to next frequency step
a - Toggle between bands (A: 650-850 MHz / B: 900-960 MHz)
r - Reset to band start
m 0|1 - Set MUXOUT: 0=ThreeState, 1=DigitalLockDetect
t - Toggle Mute-Till-Lock detect
s - Show current status
? - Show help menu

2. BasicSweep

File: examples/BasicSweep/BasicSweep.ino

General-purpose GPIO-controlled sweep with configurable frequency bands.

Features:

Simple configurable sweep implementation
VCO power control via GPIO
Choice of two preset bands (A or B)
Easy to modify for custom frequency ranges

Configuration:

Set BAND_SELECT to 'A' or 'B', or modify frequency parameters directly:

#define BAND_SELECT 'A'  // 'A' or 'B'

// Band A: 650-850 MHz, 2.0 MHz step @ +5 dBm
// Band B: 900-960 MHz, 0.2 MHz step @ +5 dBm

GPIO Control (Raspberry Pi):

Pin 6 (LOSET): Falling edge = program frequency, Rising edge = advance
Pin 7 (RESET): LOW = reset to band start
Pin 8 (VCO_CTRL): HIGH = VCO on (sweep active), LOW = VCO off

Usage:

Good starting point for custom sweep applications. Modify frequency range and output power as needed.

3. SweepMixer

File: examples/SweepMixer/SweepMixer.ino

Purpose-built sweep for mixer characterization measurements.

Specifications:

Frequency Range: 650-850 MHz (Band A)
Step Size: 2.0 MHz
Output Power: +5 dBm (fixed)
Use Case: Mixer response measurements

Features:

Fixed high output power for mixer testing
VCO power control for sweep enable/disable
Optimized for coarse frequency sweeps

GPIO Control (Raspberry Pi):

Pin 6 (LOSET): Program/advance frequency
Pin 7 (RESET): Reset to 650 MHz
Pin 8 (VCO_CTRL): Enable/disable sweep

4. SweepFilter

File: examples/SweepFilter/SweepFilter.ino

Purpose-built sweep for filter characterization with signal injection.

Specifications:

Frequency Range: 900-960 MHz (Band B)
Step Size: 0.2 MHz (fine resolution)
Output Power: Dual sweep (+5 dBm → -4 dBm)
Use Case: Filter/cavity response measurements

Features:

Automatic power toggling: Each RESET toggles between +5 dBm and -4 dBm
Dual-sweep protocol:
1. First sweep at +5 dBm (high power)
2. Second sweep at -4 dBm (low power for signal injection)
Fine frequency resolution for detailed filter characterization

GPIO Control (Raspberry Pi):

Pin 6 (LOSET): Program/advance frequency
Pin 7 (RESET): Reset to 900 MHz + toggle power level
Pin 8 (PD_CTRL): LO power-down control (HIGH=on, LOW=off)

Power Control:

Uses register 2 power-down for clean on/off switching
When LOW: Complete power-down (no signal leakage)
When HIGH: LO powered and sweep enabled

Sweep Sequence:

Start at 900 MHz, +5 dBm
Sweep to 960 MHz
Pi sends RESET → frequency resets to 900 MHz, power switches to -4 dBm
Sweep to 960 MHz at lower power
Next RESET toggles back to +5 dBm

Hardware Setup

Required Components:

Arduino (Uno, Nano, or compatible)
ADF4351 Local Oscillator module
SPI connections between Arduino and ADF4351
Raspberry Pi (for automated sweep control)

Wiring:

Arduino to ADF4351 Module (SPI):

All examples use these connections:

MOSI → ADF4351 DATA pin
SCK → ADF4351 CLK pin
Pin 10 → ADF4351 LE pin (Latch Enable)
Pin 2 → ADF4351 CE pin (Chip Enable, kept HIGH)
GND → ADF4351 GND
VCC → ADF4351 VCC (3.3V or 5V depending on module)

Arduino to Raspberry Pi (GPIO - for sweep examples):

Sweep examples (BasicSweep, SweepMixer, SweepFilter):

Pin 6 → Raspberry Pi GPIO (LOSET - Program/Advance signal)
Pin 7 → Raspberry Pi GPIO (RESET - Reset to band start)
Pin 8 → Raspberry Pi GPIO (VCO_CTRL - VCO power control)
GND → Raspberry Pi GND (common ground)

Arduino to Laptop:

All examples support serial monitoring:

USB Cable → For serial communication, monitoring, and power