INA Series Sensor

All-in-one Arduino library for Texas Instruments INA-series current / voltage / power monitors

26 chips · Two modes · API Reference · API 参考手册 · User Guide · 使用指南 · INA Monitor Tool

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Features

Broad chip coverage	INA219, INA220, INA226, INA228, INA229 (SPI), INA230–239, INA740X, INA3221, INA2227, INA4230, INA4235 — including Q1 automotive variants
Two usage modes	JSONL streaming for the NiusRobotLab_INA_monitor desktop tool, or standalone direct-read API for your own code — both can be combined
Multi-platform	Arduino AVR, ESP32 / ESP8266, RP2040 / RP2350, SAMD, STM32, megaAVR, Renesas — architectures=*
Per-channel control	INA3221 triple-channel: independent shunt resistor, enable/disable, per-channel reading
Advanced sensing	INA228/229: die temperature, energy accumulation, charge accumulation
69 ready-to-flash examples	Basic, advanced (temperature/energy), and alert-interrupt examples for every supported chip

Quick Start

Install

Arduino IDE: Sketch → Include Library → Add .ZIP Library → select the downloaded .zip.

PlatformIO: Add to platformio.ini:

lib_deps = dunknowcoding/INA Series Sensor

Mode A — JSONL Streaming (with INA Monitor)

#include <INA_Series_Sensor.h>

static InaBridge228 sensor("INA228", 0x40);

void setup() {
  Serial.begin(115200);
  sensor.begin(8, 9);  // SDA, SCL
}

void loop() {
  sensor.tick();  // Responds to START/STOP/SR commands from INA Monitor
}

Open NiusRobotLab_INA_monitor, connect the serial port, and click Start to see real-time voltage / current / power graphs.

Mode B — Standalone Direct Reading

#include <INA_Series_Sensor.h>

static InaBridge228 sensor("INA228", 0x40);

void setup() {
  Serial.begin(115200);
  sensor.begin(8, 9);
  sensor.setRshunt(0.1);  // 100 mΩ shunt
  sensor.setImax(10.0);   // 10 A max
}

void loop() {
  if (sensor.dataReady()) {
    float voltage = sensor.readBusVoltage();  // V
    float current = sensor.readCurrent();     // A
    float power   = sensor.readPower();       // W
    float temp    = sensor.readDieTemp();     // °C (INA228 only)

    Serial.print("V="); Serial.print(voltage, 3);
    Serial.print(" I="); Serial.print(current, 4);
    Serial.print(" P="); Serial.print(power, 4);
    Serial.print(" T="); Serial.println(temp, 1);
  }
  delay(100);
}

INA3221 — Multi-Channel

static InaBridge3221 sensor("INA3221", 0x40);

void setup() {
  Serial.begin(115200);
  sensor.begin(8, 9);
  sensor.setRshunt(1, 0.100);  // CH1: 100 mΩ
  sensor.setRshunt(2, 0.050);  // CH2:  50 mΩ
  sensor.setRshunt(3, 0.010);  // CH3:  10 mΩ
}

void loop() {
  if (sensor.dataReady()) {
    for (uint8_t ch = 1; ch <= 3; ch++) {
      Serial.print("CH"); Serial.print(ch);
      Serial.print(": ");
      Serial.print(sensor.readBusVoltage(ch), 3);
      Serial.print("V  ");
      Serial.print(sensor.readCurrent(ch), 4);
      Serial.println("A");
    }
    Serial.println();
  }
  delay(500);
}

Supported Chips

Bridge Class	Chips	Interface	Channels	Special Features
InaBridge219	INA219, INA220, INA220-Q1	I²C	1	—
InaBridge226	INA226, INA226-Q1, INA230–234, INA236	I²C	1	—
InaBridge228	INA228, INA228-Q1, INA237–239 (+ Q1), INA740X	I²C	1	Die temp, energy, charge
InaBridge229Spi	INA229, INA229-Q1	SPI	1	Die temp, energy, charge
InaBridge3221	INA3221, INA3221-Q1	I²C	3	Per-channel control
InaBridgeCh1	INA2227, INA4230, INA4235	I²C	1 (CH1)	—

Tested Platforms

Platform	Status	Notes
Arduino AVR (Uno, Mega, Nano)	✅ Verified	Primary test target
ESP32 / ESP32-S3 / ESP32-C3	✅ Verified	Recommended — GPIO remapping via begin(SDA, SCL)
ESP8266	✅ Compatible	IRAM_ATTR for ISR supported
RP2040 (Raspberry Pi Pico)	✅ Compatible	—
SAMD (Arduino Zero, MKR)	✅ Compatible	—
STM32 (Nucleo)	✅ Compatible	—
megaAVR (Nano Every)	✅ Compatible	—
Renesas RA (UNO R4)	✅ Compatible	—

Documentation

Document	Description
API Reference (EN)	Complete API for all Bridge classes — parameters, return values, usage examples
API 参考手册 (中文)	完整 API 参考 — 参数、返回值、使用示例
User Guide (EN)	Wiring diagrams, commercial module compatibility, INA Monitor setup, standalone usage
使用指南 (中文)	接线说明、商用模块兼容性、INA Monitor 设置、独立使用指南

Project Structure

INA_series_sensor/
├── src/
│   ├── INA_Series_Sensor.h          # Main include — pulls in everything
│   ├── InaBridge219.h/.cpp          # INA219/220 bridge
│   ├── InaBridge226.h/.cpp          # INA226 family bridge
│   ├── InaBridge228.h/.cpp          # INA228 digital family bridge
│   ├── InaBridge229Spi.h/.cpp       # INA229 SPI bridge
│   ├── InaBridge3221.h/.cpp         # INA3221 triple-channel bridge
│   ├── InaBridgeCh1.h/.cpp          # INA2227/4230/4235 CH1-only bridge
│   ├── InaBridgeUnknown.h/.cpp      # Placeholder (no sensor)
│   ├── InaJsonlProtocol.h           # JSONL serial protocol helpers
│   ├── InaSerialLineReader.h        # Non-blocking serial line reader
│   ├── InaWireCompat.h              # Portable I²C helpers
│   ├── InaSpiCompat.h               # SPI pin mapping helpers
│   └── ina/                         # Low-level driver layer
│       ├── Ina219Driver.h/.cpp      # INA219 alert driver
│       ├── Ina226Driver.h/.cpp      # INA226 alert driver
│       ├── Ina228Driver.h/.cpp      # INA228 temp/energy/alert driver
│       ├── Ina229Driver.h/.cpp      # INA229 SPI driver
│       ├── Ina3221Driver.h/.cpp     # INA3221 alert driver
│       └── ...
├── examples/                        # 69 ready-to-flash examples
└── docs/
    ├── API_EN.md                    # API reference (English)
    ├── API_CHN.md                   # API 参考手册 (中文)
    ├── USAGE_EN.md                  # User guide (English)
    └── USAGE_CHN.md                 # 使用指南 (中文)

License

MIT — see LICENSE for details.

Author

NiusRobotLab / dunknowcoding — GitHub