INA3221
Three-Channel, High-Side Current and Bus Voltage MonitorThe INA3221 is a three-channel, high-side current and bus voltage monitor from Texas Instruments. View the full INA3221 datasheet below including key specifications, electrical characteristics, absolute maximum ratings.
Official INA3221 datasheet (PDF) — the source this page was extracted from.
INA3221 Key Specifications
| Parameter | Value |
|---|---|
| Gain Error (Max) | 0.25% |
| ADC Sampling Rate | 500 kHz (±30%) typical |
| Number Of Channels | 3 |
| Package Dimensions | 4.00mm x 4.00mm, 0.65mm pitch |
| Offset Voltage (Max) | ±80 µV |
| Supply Voltage Range | 2.7V to 5.5V |
| Communication Interface | I2C / SMBus-compatible |
| Supply Current (Typical) | 350 µA |
| Bus Voltage Sensing Range | 0V to 26V |
| Programmable I2C Addresses | 4 |
| Operating Temperature Range | -40°C to +125°C |
INA3221 Overview
Part: INA3221AIRGVR — Texas Instruments
Type: Triple-Channel High-Side Current and Bus Voltage Monitor (I²C/SMBus)
Description: 26 V bus, 3-channel, 13-bit shunt and bus voltage monitor with I²C/SMBus interface, programmable alerts, ±80 μV max shunt offset, 0.25% max gain error, and 350 μA typ supply current from a 2.7–5.5 V supply.
Operating Conditions:
- Supply voltage: 2.7–5.5 V
- Operating temperature: -40 to 125 °C
- Monitored bus voltage: 0 to 26 V
Absolute Maximum Ratings:
- Max supply voltage: 6 V
- Max analog input voltage (common-mode, VPU): 26 V
- Max junction temperature: 150 °C
- Storage temperature: -65 to 150 °C
- Max input current into any pin: 5 mA
Key Specs:
- Shunt voltage input range: ±163.84 mV (40 μV LSB, 13-bit)
- Bus voltage input range: 0–26 V (8 mV LSB)
- Shunt offset voltage: ±40 μV typ, ±80 μV max (TA = 25 °C)
- Shunt gain error: 0.1% typ, 0.25% max
- Common-mode rejection: 110 dB min, 120 dB typ (VIN+ = 0 to 26 V)
- Quiescent current: 350 μA typ, 450 μA max; power-down 0.5 μA typ, 2 μA max
- ADC conversion time: 140 μs to 8.244 ms typ depending on CT setting
- Digital output VOL: 0.4 V max (SDA, Critical, Warning, PV at IOL = 3 mA; TC at IOL = 1.2 mA)
Features:
- Senses bus voltages from 0 V to 26 V
- Reports shunt and bus voltage
- Configurable averaging options
- Four programmable I²C addresses
- Programmable critical and warning alert outputs, plus power valid and timing control outputs
- Continuous and single-shot operating modes
Applications:
- Computers
- Power management
- Telecom equipment
- Battery chargers
- Power supplies
- Test equipment
- Data centers
Package:
- RGV (VQFN, 16 pins), 4.00 mm × 4.00 mm
INA3221 Features
- Senses bus voltages from 0V to 26V
- Reports shunt and bus voltage
- High accuracy:
- -Offset voltage: ±80μV (maximum)
- -Gain error: 0.25% (maximum)
- Configurable averaging options
- Four programmable addresses
- Programmable alert and warning outputs
- Power-supply operation: 2.7V to 5.5V
INA3221 Applications
INA3221 Pin Configuration
Figure 5-1. RGV Package 16-Pin VQFN Top View
Table 5-1. Pin Functions
| PIN - NAME | PIN - NO. | Type | DESCRIPTION |
|---|---|---|---|
| A0 | 5 | Digital input | Address pin. Connect to GND, SCL, SDA, or V S . Table 7-1 shows pin settings and corresponding addresses. |
| Critical | 9 | Digital output | Conversion-triggered critical alert; open-drain output. |
| GND | 3 | Analog | Ground |
| IN-1 | 11 | Analog input | Connect to load side of the channel 1 shunt resistor. Bus voltage is the measurement from this pin to ground. |
| IN+1 | 12 | Analog input | Connect to supply side of the channel 1 shunt resistor. |
| IN-2 | 14 | Analog input | Connect to load side of the channel 2 shunt resistor. Bus voltage is the measurement from this pin to ground. |
| IN+2 | 15 | Analog input | Connect to supply side of the channel 2 shunt resistor. |
| IN-3 | 1 | Analog input | Connect to load side of the channel 3 shunt resistor. Bus voltage is the measurement from this pin to ground. |
| IN+3 | 2 | Analog input | Connect to supply side of the channel 3 shunt resistor. |
| PV | 10 | Digital output | Power valid alert; open-drain output. |
| SCL | 6 | Digital input | Serial bus clock line; open-drain input. |
| SDA | 7 | Digital I/O | Serial bus data line; open-drain input/output. |
| TC | 13 | Digital output | Timing control alert; open-drain output. |
| VPU | 16 | Analog input | Pull-up supply voltage used to bias power valid output circuitry. |
| VS | 4 | Analog | Power supply, 2.7V to 5.5V. |
| Warning | 8 | Digital output | Averaged measurement warning alert; open-drain output. |
| Thermal Pad | - | - | This pad must be connected to ground or left floating. |
Table 5-1. Pin Functions
INA3221 Electrical Characteristics
at T A = 25°C, VS = 3.3V, VIN+ = 12V, V SHUNT = (VIN+) - (VIN-) = 0mV, and VBUS = VIN- = 12V (unless otherwise noted)
| PARAMETER | TEST CONDITIONS | MIN TYP | MAX | UNIT | ||
|---|---|---|---|---|---|---|
| INPUT | ||||||
| V SHUNT | Shunt voltage input | -163.84 | 163.8 | mV | ||
| V BUS | Bus voltage input | 0 | 26 | V | ||
| CMR | Common-mode rejection | V IN+ = 0V to +26V | 110 120 | dB | ||
| V | ±40 | ±80 | μV | |||
| OS | Shunt offset voltage, RTI (1) | T A = -40°C to +125°C | 0.1 | 0.5 | μV/°C | |
| PSRR | vs power supply, V S = 2.7V to 5.5V | 15 | μV/V | |||
| V | (1) | ±8 | ±16 | mV | ||
| OS | Bus offset voltage, RTI | T A = -40°C to +125°C | 80 | μV/°C | ||
| PSRR | vs power supply | 0.5 | mV/V | |||
| I IN+ | Input bias current at IN+ | 10 | μA | |||
| I IN- | Input bias current at IN- | 10 || 670 | μA || kΩ | |||
| Input leakage (2) | (IN+ pin) + (IN- pin), power-down mode | 0.1 | 0.5 | μA | ||
| DC ACCURACY | ADC native resolution | Shunt voltage | 13 40 | Bits μV | ||
| 1LSB step size Shunt voltage gain error | Bus voltage | 8 0.1% | 0.25% | mV | ||
| T A = -40°C to +125°C | 10 0.1% | 50 0.25% | ppm/°C | |||
| Bus voltage gain error | T A = -40°C to +125°C | 10 | 50 | ppm/°C | ||
| DNL | Differential nonlinearity | CT bit = 000 CT bit = 001 | ±0.1 140 204 | 154 224 | LSB | |
| CT bit = 010 CT bit = 011 | 332 588 | 365 646 | μs | |||
| t CONVERT | ADC conversion time | CT bit = 100 CT bit = 101 | 1.1 2.116 | 1.21 2.328 | ||
| CT bit = 110 CT bit = 111 | 4.156 8.244 | 4.572 9.068 | ms | |||
| SMBus | ||||||
| SMBus timeout (3) | 28 | 35 | ms | |||
| DIGITAL INPUT/OUTPUT | DIGITAL INPUT/OUTPUT | DIGITAL INPUT/OUTPUT | DIGITAL INPUT/OUTPUT | DIGITAL INPUT/OUTPUT | DIGITAL INPUT/OUTPUT | DIGITAL INPUT/OUTPUT |
| C I | Input capacitance | 3 | pF |
at T A = 25°C, VS = 3.3V, VIN+ = 12V, V SHUNT = (VIN+) - (VIN-) = 0mV, and VBUS = VIN- = 12V (unless otherwise noted)
| PARAMETER | PARAMETER | PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT |
|---|---|---|---|---|---|---|---|
| Leakage input current | Leakage input current | Leakage input current | 0V ≤ V IN ≤ V S | 0.1 | 1 | μA | |
| V IH | High-level input voltage | High-level input voltage | 0.7 (V S ) | 6 | V | ||
| V IL | Low-level input voltage | Low-level input voltage | -0.5 | 0.3 (V S ) | V | ||
| V OL | Low-level output voltage | SDA, critical, warning, PV | V S > +2.7V, I OL = 3mA | 0 | 0.4 | V | |
| V OL | Low-level output voltage | TC | V S > +2.7V, I OL = 1.2mA | 0 | 0.4 | V | |
| V hys | Hysteresis voltage | Hysteresis voltage | 500 | 500 | mV | ||
| POWER SUPPLY | POWER SUPPLY | POWER SUPPLY | POWER SUPPLY | POWER SUPPLY | POWER SUPPLY | POWER SUPPLY | POWER SUPPLY |
| Quiescent current | Quiescent current | Quiescent current | 350 | 450 | μA | ||
| Power-down mode | 0.5 | 2 | μA | ||||
| Power-on reset threshold | Power-on reset threshold | Power-on reset threshold | 2 | V |
INA3221 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
| MIN | MAX | UNIT | |||
|---|---|---|---|---|---|
| Voltage | Supply, V S | Supply, V S | 6 | V | |
| Analog inputs | Differential (V IN+ ) - (V IN- ) (2) | -26 | 26 | V | |
| Analog inputs | Common-mode (V IN+ ) + (V IN- ) / 2 | -0.3 | 26 | V | |
| Analog inputs | VPU | VPU | 26 | V | |
| Digital outputs | Critical, warning, power valid | Critical, warning, power valid | 6 | V | |
| Digital outputs | Timing control | Timing control | 26 | V | |
| Serial bus | Data line, SDA | Data line, SDA | (GND - 0.3) | 6 | V |
| Serial bus | Clock line, SCL | Clock line, SCL | (GND - 0.3) | 6 | V |
| Current | Input, into any pin | Input, into any pin | 5 | mA | |
| Current | Open-drain, digital output | Open-drain, digital output | 10 | mA | |
| Temperature | Operating, T A | Operating, T A | -40 | 125 | °C |
| Temperature | Junction, T J | Junction, T J | 150 | °C | |
| Temperature | Storage, T stg | Storage, T stg | -65 | 150 | °C |
INA3221 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
| MIN | NOM | MAX | UNIT | |
|---|---|---|---|---|
| Operating supply voltage | 2.7 | 5.5 | V | |
| Operating temperature, T A | -40 | 125 | °C |
INA3221 Thermal Information
| THERMAL | METRIC (1) | INA3221 RGV (VQFN) 16 PINS | UNIT |
|---|---|---|---|
| R θJA | Junction-to-ambient thermal resistance | 36.5 | °C/W |
| R θJC(top) | Junction-to-case (top) thermal resistance | 42.7 | °C/W |
| R θJB | Junction-to-board thermal resistance | 14.7 | °C/W |
| ψ JT | Junction-to-top characterization parameter | 0.5 | °C/W |
| ψ JB | Junction-to-board characterization parameter | 14.8 | °C/W |
| R θJC(bot) | Junction-to-case (bottom) thermal resistance | 3.3 | °C/W |
INA3221 Typical Application
INA3221 is a three-channel current and bus voltage monitor with I 2 C/SMBUS-compatible interface. It features programmable conversion times and averaging modes and offers both critical and warning alerts to detect multiple programmable out-of-range conditions for each channel.
INA3221 Package Information
| PART NUMBER | PACKAGE (1) | PACKAGE SIZE (2) |
|---|---|---|
| INA3221 | RGV (VQFN, 16) | 4.00mm × 4.00mm |
- (1) For all available packages, see the package option addendum at the end of the datasheet.
- (2) The package size (length × width) is a nominal value and includes pins, where applicable.
Typical Application
Variants on the same datasheet
These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.
| Part Number | Manufacturer | Package |
|---|---|---|
| INA3221AIRGVR | Texas Instruments | QFN-16-EP(4x4) |
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