INA237 - 85V 16-Bit I2C Power Monitor | Texas Instruments
MPN： INA237 ✓ 啟用中INA237 概覽
A digital power monitor is an integrated power management IC that digitizes shunt voltage, bus voltage, and computed power, then reports values over a serial bus such as I2C. Within the power-monitoring hierarchy, the INA237 sits in the current/voltage/power monitor family, complementing supervisors, hot-swap controllers, and DC-DC converters in modern power management systems.
Key features include high-resolution 16-bit delta-sigma conversion, current-monitoring accuracy with ±50 uV maximum offset voltage, ±0.02 uV/C maximum offset drift, and ±0.3% gain error. The 85 V common-mode withstand is a major differentiator, allowing direct monitoring of 48 V telecom, server, and industrial buses without additional level-shifting circuitry.
The delta-sigma architecture provides excellent noise performance and allows configurable conversion times and averaging, trading conversion speed for accuracy. Registers report shunt voltage, bus voltage, current, and power directly, simplifying firmware. The integrated alert pin supports configurable alerts including overcurrent and overvoltage thresholds.
Typical applications include 48 V server and datacenter power-rail monitoring, telecom base-station power supplies, industrial 24-85 V motor and automation systems, and battery-management telemetry in test equipment. The wide common-mode range covers virtually all common industrial and datacenter bus voltages.
Design tip: choose the shunt resistor so full-scale load current generates a shunt voltage well within the ±163.84 mV range, balancing accuracy (larger shunt) against power loss (smaller shunt). For applications needing tighter accuracy, the pin-compatible INA238 offers improved offset and gain error in the same footprint.
直接替換替代品，適用於 INA237 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
INA238
✅ 直接替換📋 參考替代品（不在目錄中）
INA237AQDGSRQ1
✅ 直接替換📋 參考替代品（不在目錄中）
INA239
✅ 直接替換📋 參考替代品（不在目錄中）
INA228
✅ 直接替換📋 參考替代品（不在目錄中）
INA226AIDGSR-Q1
⚡ 相同封裝 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →INA237 規格
| ADC Resolution | 16-bit delta-sigma |
| Common-Mode Voltage Range | -0.3 V to 85 V |
| Full-Scale Differential Input | ±163.84 mV or ±40.96 mV |
| Offset Voltage | ±50 uV (maximum) |
| Offset Drift | ±0.02 uV/C (maximum) |
| Gain Error | ±0.3% |
| 介面 | I2C |
| Measured Parameters | Current, voltage, power |
| Alert Function | Yes (configurable alert pin) |
| Sense Configuration | High-side or low-side |
| 封裝 | 10-VSSOP (DGS) |
| 安裝類型 | Surface Mount |
| 工作溫度 | -40C to +125C |
| RoHS 狀態 | Compliant |
| Automotive Qualification | INA237-Q1 variant is AEC-Q100 qualified |
INA237 腳位配置
| 腳位 1 | A0 — I2C address select |
| 腳位 2 | SCL — I2C serial clock |
| 腳位 3 | SDA — I2C serial data |
| 腳位 4 | ALERT — Alert output (open-drain) |
| 腳位 5 | GND — Ground reference |
| 腳位 6 | IN- — Shunt voltage negative input |
| 腳位 7 | IN+ — Shunt voltage positive input |
| 腳位 8 | VBUS — Bus voltage sense input (up to 85 V) |
| 腳位 9 | VS — Power supply |
| 腳位 10 | A1 — I2C address select |
典型應用
INA237 適用於 6 應用s: 48V Server and Datacenter Power Monitoring, Telecom Power Supplies, Industrial Automation and Motor Drives, Battery Management and Energy Telemetry, Automotive Power Monitoring, Test and Measurement Instrumentation.
48V Server and Datacenter Power Monitoring
The INA237 fits 48 V server and datacenter power-rail monitoring because its -0.3 V to 85 V common-mode range directly tolerates the nominal 48 V bus plus transients without level shifting. Placed across a shunt on the 48 V feed, its 16-bit delta-sigma ADC with ±50 uV offset and ±0.3% gain error resolves milliamp-level load steps, while the I2C interface reports current, bus voltage, and power directly to the BMC or power controller.
推薦
Telecom Power Supplies
Telecom -48 V and 48 V distribution rails demand a monitor with high common-mode withstand, and the INA237's 85 V rating provides wide margin for surge-prone telecom environments. Its high- or low-side sensing flexibility suits both distribution bus and card-level monitoring. The configurable alert pin raises immediate fault flags on overcurrent events, reducing response time compared with polling-only schemes, and averaging modes let designers trade conversion rate for noise-free accuracy.
推薦
Industrial Automation and Motor Drives
In industrial 24 V to 85 V automation systems and motor-drive DC buses, the INA237 provides continuous current, voltage, and power telemetry over I2C. The ±163.84 mV full-scale input accommodates standard mΩ-class shunts at drive load currents, while the -0.3 V to 85 V common-mode range covers typical industrial bus voltages including 48 V and 60 V systems. Alert thresholds enable fast overcurrent detection for predictive maintenance and protection logic.
推薦
Battery Management and Energy Telemetry
The INA237 supports battery pack current and voltage telemetry in high-voltage storage systems where the bus can reach 85 V. Its delta-sigma converter provides stable readings across temperature with only ±0.02 uV/C offset drift, and configurable conversion/averaging times let firmware optimize between sample rate and resolution. Power is computed on-chip and read over I2C, offloading the host MCU in battery management units and energy-monitoring nodes.
推薦
Automotive Power Monitoring
For automotive 12 V and 48 V mild-hybrid rails, the AEC-Q100 qualified INA237-Q1 (INA237AQDGSRQ1) provides the same 85 V, 16-bit I2C monitoring with automotive-grade qualification. It suits body-controller, ADAS power-supply, and zonal-fuse monitoring designs where current, voltage, and power must be reported to a gateway ECU over I2C. The alert pin supports fast overcurrent detection for diagnostic fault handling.
推薦
Test and Measurement Instrumentation
Bench instruments and programmable loads use the INA237 as an inline power-measurement front end. SparkFun and Adafruit breakout boards popularize it for this purpose: up to 85 VDC common-mode, high- or low-side measurement, and 16-bit precision from milliamps to amps over I2C. Configurable gain (±163.84 mV or ±40.96 mV full-scale) lets the same hardware adapt to different shunt values, and averaging improves reading stability for logging applications.
推薦
推薦產品摘要
工程參考資料，適用於 INA237 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | INA238 | INA237AQDGSRQ1 | INA239 | INA228 |
|---|---|---|---|---|---|
| Package | 10-VSSOP (DGS) | 10-VSSOP (DGS) - same | 10-VSSOP (DGS) - same | 10-VSSOP (DGS) - same | 10-VSSOP (DGS) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| ADC Resolution | 16-bit | 16-bit | 16-bit | 16-bit | 20-bit |
| Common-Mode Voltage | -0.3 V to 85 V | -0.3 V to 85 V | -0.3 V to 85 V | 85 V | 85 V |
| Energy/Charge Measurement | No | No | No | No | Yes |
| AEC-Q100 Qualification | No (standard grade) | No | Yes (AEC-Q100) | No | No |
主要差異化特點
- 85 V common-mode withstand (對比INA226AIDGSR-Q1)
- Cost-effective accuracy tier (對比INA238)
- Simplified feature set vs INA228 (對比INA228)
設計說明
Route the shunt sense traces as a Kelvin pair directly from the shunt resistor pads to the IN+ and IN- pins. Any trace resistance in the sense path adds gain error directly to the measurement. Keep the sense traces away from switching-node copper and guard them with ground. Place a 0.1 uF differential capacitor close to IN+/IN- for input filtering, and decouple VS with 0.1 uF plus 1 uF per TI datasheet recommendations.
Size the shunt resistor so full-scale load current develops a voltage within ±163.84 mV (or ±40.96 mV for higher resolution on lower currents). Balance shunt power dissipation (I^2R) against accuracy: a larger shunt improves LSB resolution but wastes power and heats the sense element, increasing thermal offset drift on the PCB. For a 10 A rail, a 5 mOhm shunt gives 50 mV full-scale drop with 2.5 W loss.
The ALERT pin is open-drain and requires a pull-up resistor to the I2C logic supply. When using I2C digital isolators, note from TI E2E discussions that the INA237 expects a logic-low level below 0.4 V - isolator outputs with 0.9 V logic-low levels are out of specification. Also remember that the VBUS pin senses up to 85 V directly; never exceed this absolute rating even during transients.
合規資訊
RoHS compliant per TI product page. AEC-Q100 qualified INA237-Q1 variant (INA237AQDGSRQ1) available separately. REACH and halogen-free status not stated in provided data.
