The part number " INA3221AIRGVR " refers to a specific product manufactured by Texas Instruments (TI). It is a multi-channel current/voltage monitor with an I2C interface , specifically used for monitoring Power rails and current shunt voltages. Below, I will provide detailed specifications for the pins, encapsulation, and their respective functions, as well as an FAQ about the part.
Package and Pinout Description
The INA3221AIRGVR is housed in a VQFN-16 package, which means it has 16 pins in a Very Thin Quad Flat No-lead (VQFN) form factor. This device is primarily used for monitoring voltage and current in multi-rail systems and offers high accuracy with a precision I2C interface.
Pin Functions
Below is the list of pin functions for the INA3221AIRGVR in the VQFN-16 package:
Pin Number Pin Name Function Description 1 VSS Ground connection for the INA3221 device. 2 SDA I2C Serial Data input/output, used for communication with the device. 3 SCL I2C Serial Clock input, used for synchronization of data transfer. 4 ALERT Open-drain output, used to indicate an alarm condition. 5 V+ (Pin 1) Positive voltage input for channel 1. 6 V+ (Pin 2) Positive voltage input for channel 2. 7 V+ (Pin 3) Positive voltage input for channel 3. 8 VSS Ground connection for the INA3221 device (again, pin 8). 9 V+ (Pin 4) Positive voltage input for channel 4 (if applicable). 10 VSS Ground connection for the INA3221 device. 11 VCC Power supply for the INA3221 device (typically +3.3V or +5V). 12 RESET Reset input pin to reset the device. 13 VDD Positive voltage supply (input). 14 SENSE1 Current sense input for the first channel (SENSE1). 15 SENSE2 Current sense input for the second channel (SENSE2). 16 SENSE3 Current sense input for the third channel (SENSE3).This 16-pin setup covers the main voltage input pins for the 3 voltage monitoring channels, I2C communication pins (SDA and SCL), as well as various ground and power supply connections.
Common FAQ for INA3221AIRGVR
Q1: What is the purpose of the INA3221AIRGVR?A1: The INA3221AIRGVR is a high-precision, multi-channel current and voltage monitor used to measure the voltage of up to three power rails, while also measuring the current flowing through them, via I2C communication.
Q2: How many voltage inputs does the INA3221 have?A2: The INA3221 has 3 voltage inputs, labeled as V+ (Pin 1), V+ (Pin 2), and V+ (Pin 3), which can be used to measure the voltages on three different power rails.
Q3: What does the ALERT pin do?A3: The ALERT pin is an open-drain output used to signal alarm conditions based on preset thresholds, such as under-voltage or over-voltage conditions on the monitored rails.
Q4: How does the I2C communication work on this device?A4: The device communicates with a microcontroller through the I2C interface using the SDA (data line) and SCL (clock line). The I2C bus allows multiple devices to communicate using a two-wire system.
Q5: What is the recommended operating voltage for the INA3221?A5: The INA3221 operates typically at 3.3V or 5V, which is supplied via the VCC pin (Pin 11).
Q6: What does the RESET pin do?A6: The RESET pin (Pin 12) is used to reset the device. It forces the INA3221 to restart its internal state machine and reinitialize its functions.
Q7: How can I use the current sense inputs (SENSE1, SENSE2, SENSE3)?A7: The current sense inputs (Pin 14, Pin 15, Pin 16) are used to measure the voltage drop across a sense resistor, which corresponds to the current flowing through the load.
Q8: How many channels of current and voltage does the INA3221 support?A8: The INA3221 supports three channels of current and voltage monitoring, each with dedicated sense inputs for current and voltage measurement.
Q9: What is the typical application of the INA3221AIRGVR?A9: Typical applications include power supply monitoring, battery-powered devices, and systems that require real-time voltage and current measurement to monitor power health.
Q10: Can I use the INA3221 with a 5V system?A10: Yes, the INA3221 can be used in both 3.3V and 5V systems. The VCC pin allows for a supply voltage of 3.3V or 5V.
Q11: What type of package does the INA3221 come in?A11: The INA3221 comes in a VQFN-16 package, which is a 16-pin very thin quad flat no-lead package.
Q12: What are the current measurement ranges?A12: The current measurement range depends on the sense resistor and the maximum voltage drop across it. The device can handle large current flows when a suitable sense resistor is chosen.
Q13: How do I set the alarm thresholds?A13: The alarm thresholds for voltage and current can be configured using the I2C interface by writing the desired values to the corresponding registers in the device.
Q14: Can I monitor multiple power rails with this device?A14: Yes, you can monitor three separate power rails independently with the INA3221, each with its own voltage and current measurement.
Q15: What is the function of the SENSE pins?A15: The SENSE pins are used for monitoring the voltage drop across an external sense resistor, which allows the device to calculate the current flowing through the respective channel.
Q16: Is the INA3221 configurable for different voltage ranges?A16: Yes, the INA3221 allows you to configure the voltage monitoring range via the I2C interface by adjusting the corresponding registers.
Q17: How do I use the ALERT function effectively?A17: You can configure the ALERT pin to activate under certain conditions, such as when voltage or current exceeds or falls below a set threshold, which can help in triggering external responses.
Q18: What is the maximum voltage rating for the INA3221’s V+ input pins?A18: The V+ input pins can withstand a maximum voltage of 26V, but it’s always recommended to keep it within the device's specified operating range to avoid damage.
Q19: Can the INA3221 be used in industrial automation applications?A19: Yes, the INA3221 is well-suited for industrial automation applications due to its accuracy, multi-channel measurement, and I2C interface for easy integration.
Q20: What is the power consumption of the INA3221 device?A20: The INA3221 has low power consumption, typically consuming less than 1mA when operating, which makes it ideal for battery-powered systems.
Conclusion
The INA3221AIRGVR is a highly versatile, multi-channel current and voltage monitor designed to work in various applications requiring precise monitoring of multiple power rails. It is easy to interface with microcontrollers via I2C, and its compact VQFN-16 package makes it suitable for space-constrained designs.
