INA381A3
Current Sense Amplifier with Integrated ComparatorThe INA381A3 is a current sense amplifier with integrated comparator from Texas Instruments. View the full INA381A3 datasheet below including electrical characteristics, absolute maximum ratings.
Overview
Part: INA381 — Texas Instruments
Type: High-Speed, Current Sense Amplifier With Integrated Comparator
Description: The INA381 is a 26-V common-mode current-sensing amplifier with an integrated high-speed comparator, capable of detecting overcurrent conditions by measuring voltage across a shunt resistor and comparing it to a user-defined threshold.
Operating Conditions:
- Supply voltage: 2.7 V to 5.5 V
- Operating temperature: -40 to +125 °C
- Common-mode input voltage: -0.2 V to 26 V
Absolute Maximum Ratings:
- Max supply voltage: 6 V
- Max junction temperature: 150 °C
- Max storage temperature: 150 °C
Key Specs:
- Common-mode input range: -0.2 V to +26 V
- Offset voltage (VCM = 12 V, TA = 25°C): ±500 μV (maximum)
- Offset voltage (VCM = 0 V, TA = 25°C): ±150 μV (maximum)
- Offset voltage drift: 1 μV/°C (maximum)
- Gain error (TA = 25°C): ±1% (maximum)
- Gain error drift: 20 ppm/°C (maximum)
- Quiescent current (VSENSE = 10 mV, TA = +25°C): 250 μA (typical), 350 μA (maximum)
- Comparator propagation delay (CMPIN overdrive = 20 mV): 0.4 μs (typical), 1 μs (maximum)
- Comparator hysteresis: 50 mV
Features:
- High accuracy amplifier with low offset voltage and drift
- Available amplifier gains: 20 V/V, 50 V/V, 100 V/V, 200 V/V
- Open-drain comparator with 50 mV hysteresis
- Alert threshold set through external reference voltage
- Supports transparent and latching comparator modes
- Fast alert response time
Applications:
- Merchant network and server PSU
- Merchant DC/DC
- DC-input BLDC motor drive
- Cordless power tool
- Headsets, headphones and earbuds
Package:
- VSSOP (10) - 3.00 mm × 3.00 mm
- WSON (8) - 2.00 mm × 2.00 mm
Features
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1 · Common-mode input range: -0.2 V to +26 V
-
High accuracy amplifier:
-
-Offset voltage at TA = 25°C
-
-500 μV (maximum) at VCM = 12 V
-
-150 μV (maximum) at VCM = 0 V
-
-Offset voltage drift: 1 μV/°C (maximum)
-
-Gain error: 1% (maximum) at 25°C
-
-Gain error drift: 20 ppm/°C (maximum)
-
Available amplifier gains:
-
Open-drain comparator:
-
-Hysteresis: 50 mV
-
-Propagation delay: 400 ns (typ)
-
-Alert threshold set through external reference voltage
-
-Supports transparent and latching modes
-
Packages: VSSOP-10 and WSON-8
-
INA381A1: 20 V/V
-
INA381A2: 50 V/V
-
INA381A3: 100 V/V
-
INA381A4: 200 V/V
Applications
- Merchant network and server PSU
- Merchant DC/DC
- DC-input BLDC motor drive
- Cordless power tool
- Headsets, headphones and earbuds
Pin Configuration
Electrical Characteristics
at TA = 25°C, VSENSE = VIN+ - VIN= 10 mV, VS = 5 V, VIN+ = 12 V, and CMPREF = 2 V (unless otherwise noted)
| PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT | |
|---|---|---|---|---|---|---|
| INPUT | ||||||
| CMRR | Common-mode rejection ratio, RTI (1) | V IN+ = 0 V to 26 V, T A = -40°C to +125°C | 84 | 100 | dB | |
| V | Offset voltage, RTI (1) | V IN+ = 12 V, V IN- = 12 V | ±100 | ±500 | ||
| OS | V IN+ = 0 V, V IN- = 0 V | ±25 | ±150 | μ V | ||
| dV OS /dT | Offset voltage drift, RTI (1) | T A = -40°C to +125°C | 0.1 | 1 | μ V/°C | |
| PSRR | Power-supply rejection ratio | V S = 2.7 V to 5.5 V, T A = -40°C to +125°C | ±8 | ±40 | μ V/V | |
| I B | Input bias current | V SENSE = 0 mV, I B+ , I B- | 80 | μ A | ||
| I OS | Input offset current | V SENSE = 0 mV | ±0.05 | μ A | ||
| OUTPUT | Gain | INA381A1 | 20 | |||
| G | INA381A2 | 50 | ||||
| G | INA381A3 | 100 | V/V | |||
| G | INA381A4 | 200 | ||||
| E G | Gain error | VOUT = 0.5 V to V S - 0.5 V | ±0.1% | ±1% | ||
| Gain error drift Nonlinearity error | T A = -40°C to +125°C V OUT = 0.5 V to V S - 0.5 V | 1.5 ±0.01% | 20 | ppm/°C | ||
| Maximum capacitive load | No sustained oscillation | 1 | nF | |||
| VOLTAGE | OUTPUT | |||||
| Swing to V S power-supply rail | R L = 10 k Ω to GND, T A = -40°C to +125°C | V S - 0.02 | V S - 0.05 | V | ||
| Swing to GND (2) | R L = 10 k Ω to GND, T A = -40°C to +125°C | V GND + 0.0005 | V GND + 0.005 | V | ||
| FREQUENCY RESPONSE | FREQUENCY RESPONSE | |||||
| BW | Bandwidth | INA381A1 INA381A2 INA381A3 INA381A4 | 350 210 150 105 | kHz kHz kHz kHz | ||
| SR | Slew rate | 2 | V/μs | |||
| NOISE | Voltage noise density | 40 | nV/ √ Hz | |||
| COMPARATOR | ||||||
| t p | Propagation delay time, comparator only | CMPIN Input overdrive = 20 mV | 0.4 | 1 | μs | |
| Large-signal propagation delay, comparator only | CMPIN step = 0.5 V to 4.5, V CMPREF = 4 V | 0.4 | 2 | μs | ||
| Small-signal total alert propogation delay, comparator and amplifier | Input overdrive = 1 mV | 2 | 5 | μs | ||
| Slew rate limited total alert propagation delay, comparator and amplifier | V OUT = 0.5 V to 4.5, V CMPREF = 4 V | 3 | 10 | μs | ||
| V OS | Comparator offset voltage | ±1 | ±5 | mV | ||
| HYS | Hysteresis | 50 | mV | |||
| V IH | High-level input voltage | 1.4 | 6 | V | ||
| V IL | Low-level input voltage | 0 | 0.4 | V | ||
| V OL | Alert low-level output voltage | I OL = 3 mA | 70 | 300 | mV | |
| ALERT pin leakage input current | V OH = 3.3 V | 0.1 | 1 | μ A | ||
| Digital leakage input current | 0 ≤ V IN ≤ V S | 1 | μ A | |||
| POWER | SUPPLY | |||||
| V SENSE = 10 mV, T A = +25°C | 250 | 350 | μ A | |||
| I Q | Quiescent current | T A = -40°C to +125°C | 450 |
Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
| MIN | MAX | UNIT | |||
|---|---|---|---|---|---|
| V S | Supply voltage | Supply voltage | 6 | V | |
| V IN+ ,V IN- | Analog inputs (IN+, IN-) | Differential (V IN+ ) - (V IN- ) (2) | -26 | 26 | V |
| V IN+ ,V IN- | Analog inputs (IN+, IN-) | Common-mode (3) | GND - 0.3 | 26 | V |
| V I | Analog input | CMPIN | GND - 0.3 | (V S ) + 0.3 | V |
| V I | Analog input | CMPREF | GND - 0.3 | (V S ) + 0.3 | V |
| V O | Analog output | OUT | GND - 0.3 | (V S ) + 0.3 | V |
| Digital input | RESET | GND - 0.3 | (V S ) + 0.3 | V | |
| Digital output | ALERT | GND - 0.3 | 6 | V | |
| T J | Junction temperature | Junction temperature | 150 | °C | |
| T stg | Storage temperature | Storage temperature | -65 | 150 | °C |
Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
| MIN | NOM | MAX | UNIT | ||
|---|---|---|---|---|---|
| V CM | Common-mode input voltage | -0.2 | 12 | 26 | V |
| V S | Operating supply voltage | 2.7 | 5 | 5.5 | V |
| T A | Operating free-air temperature | -40 | 125 | °C |
Thermal Information
| INA381 | INA381 | ||
|---|---|---|---|
| THERMAL METRIC (1) | THERMAL METRIC (1) | DGS (VSSOP) | DSG (WSON) |
| 10 PINS | 8 PINS | ||
| R θ JA | Junction-to-ambient thermal resistance | 188.6 | 77 |
| R θ JC(top) | Junction-to-case (top) thermal resistance | 78.1 | 96.5 |
| R θ JB | Junction-to-board thermal resistance | 111.0 | 43.4 |
| Ψ JT | Junction-to-top characterization parameter | 17.5 | 5.4 |
| Ψ JB | Junction-to-board characterization parameter | 109.2 | 43.6 |
| R θ JC(bot) | Junction-to-case (bottom) thermal resistance | N/A | 18.8 |
Typical Application
Related Variants
The following components are covered by the same datasheet.
| Part Number | Manufacturer | Package |
|---|---|---|
| INA381 | Texas Instruments | — |
| INA381A1 | Texas Instruments | WSON-8 |
| INA381A2 | Texas Instruments | WSON-8 |
| INA381A3IDGSR | Texas Instruments | — |
| INA381A3IDGSR.B | Texas Instruments | — |
| INA381A3IDGST | Texas Instruments | — |
| INA381A3IDSGR | Texas Instruments | WSON-8(2x2) |
| INA381A3IDSGR.B | Texas Instruments | — |
| INA381A3IDSGT | Texas Instruments | VSSOP-10 |
| INA381A4 | Texas Instruments | WSON-8 |
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