Overview
The INA237-Q1, produced by Texas Instruments, is an ultra-precise digital power monitor designed specifically for current-sensing applications. This device features a 16-bit delta-sigma ADC and is compliant with the AEC-Q100 standard, ensuring high reliability in automotive and other demanding environments. It measures current, bus voltage, temperature, and power, performing the necessary calculations in the background. The integrated temperature sensor offers ±1°C accuracy at 25°C, which is useful for monitoring both die and ambient temperatures. The device operates from a 2.7-V to 5.5-V supply and supports common-mode voltages from –0.3 V to +85 V, making it versatile for various high-voltage applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage (VS) | 2.7 | 5.5 | V | |
| Quiescent Current (IQ) | 640 | 750 | µA | |
| Shutdown Current (IQSD) | 5 | µA | ||
| Temperature Range | –40 | +125 | °C | |
| Temperature Accuracy | ±1 | °C (at 25°C) | ||
| Full-Scale Differential Input | ±163.84 | ±40.96 | mV | |
| Common-Mode Voltage Range | –0.3 | +85 | V | |
| ADC Conversion Time | 50 µs | 4.12 ms | ||
| Sample Averaging | 1x | 1024x | ||
| Input Bias Current | 2.5 nA | |||
| I2C Interface | 2.94 MHz |
Key Features
- High-Resolution ADC: 16-bit delta-sigma ADC for precise current, voltage, and temperature measurements.
- Programmable Conversion Time and Averaging: Conversion times from 50 µs to 4.12 ms and sample averaging from 1x to 1024x to reduce noise.
- Wide Common-Mode Range: Supports common-mode voltages from –0.3 V to +85 V.
- Low Offset and Gain Drift: Ensures accurate measurements without the need for multi-temperature calibration.
- Integrated Temperature Sensor: ±1°C accurate for die temperature measurement.
- Low Input Bias Current: Allows the use of larger current-sense resistors for accurate micro-amp range measurements.
- Fast Alert Response: 75 µs response time for alert signals.
- I2C Interface: 2.94 MHz high-speed I2C interface with 16 pin-selectable addresses.
- Functional Safety-Capable: Designed to meet functional safety requirements.
Applications
- Automotive Battery Management Systems: Ideal for precise monitoring in automotive battery systems.
- EV/HEV Applications: Suitable for electric and hybrid electric vehicle current sensing.
- DC/DC Converters and Power Inverters: Used in power conversion and inversion applications requiring high precision.
- ADAS Domain Controllers: Applicable in advanced driver-assistance systems (ADAS) for precise power monitoring.
Q & A
- What is the primary function of the INA237-Q1?
The INA237-Q1 is an ultra-precise digital power monitor designed for current-sensing applications, measuring current, bus voltage, temperature, and power.
- What is the operating voltage range of the INA237-Q1?
The device operates from a 2.7-V to 5.5-V supply.
- What is the accuracy of the integrated temperature sensor?
The integrated temperature sensor is ±1°C accurate at 25°C.
- What is the range of the full-scale differential input?
The full-scale differential input range is ±163.84 mV or ±40.96 mV.
- What is the common-mode voltage range supported by the INA237-Q1?
The device supports common-mode voltages from –0.3 V to +85 V.
- How does the INA237-Q1 reduce noise in measurements?
The device allows for programmable conversion times from 50 µs to 4.12 ms and sample averaging from 1x to 1024x to reduce noise.
- What is the typical quiescent current of the INA237-Q1?
The typical quiescent current is 640 µA.
- What is the maximum shutdown current of the INA237-Q1?
The maximum shutdown current is 5 µA.
- What type of interface does the INA237-Q1 use for communication?
The device uses a 2.94 MHz high-speed I2C interface with 16 pin-selectable addresses.
- In what applications is the INA237-Q1 commonly used?
The INA237-Q1 is commonly used in automotive battery management systems, EV/HEV applications, DC/DC converters, power inverters, and ADAS domain controllers.
