INA139NA/3K-Q1 - High-Side Current Shunt Monitor 40V SOT-23-5 | TI
MPN: INA139NA/3K-Q1 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.45 | $0.45 |
| 10 | $0.41 | $4.10 |
| 100 | $0.36 | $36.00 |
| 500 | $0.33 | $165.00 |
| 1,000 | $0.3 | $300.00 |
| 3,000 | $0.28 | $840.00 |
Drop-in alternatives for INA139NA/3K-Q1 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
INA169NA/3K
β Drop-Inβ In Stock
$0.32 / Unit
View Datasheet βINA139NA/250
β Drop-Inπ Reference alternative (not in catalog)
INA139AQDBVRQ1
β Drop-Inπ Reference alternative (not in catalog)
INA138NA/3K
β Drop-Inπ Reference alternative (not in catalog)
INA168NA/3K
β Drop-Inπ Reference alternative (not in catalog)
INA139NA/3K-Q1 Maximum Ratings & Electrical Characteristics
| Function | High-Side Current Shunt Monitor |
| Input Common-Mode Voltage Range | 2.7 V to 40 V |
| Supply Voltage Range | 2.7 V to 40 V |
| Bandwidth | 440 kHz |
| Quiescent Current | 60 uA (typ) |
| Output Type | Current output, converted to voltage via external resistor RL |
| Gain Setting | Single external resistor (transimpedance via RL) |
| Measurement Type | Unipolar, high-side |
| Supply and Common-Mode Independence | Yes, independent voltages |
| Operating Temperature Range | -40C to +125C |
| Package | SOT-23 (DBV), 5 pins |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Packaging | Tape and Reel (/3K, 3000 units) |
| MSL Level | [DATA_NEEDED: MSL level] |
INA139NA/3K-Q1 Pin Configuration
| Pin 1 | OUT β Current output; connect resistor RL to ground to convert output current to voltage |
| Pin 2 | GND β Ground reference |
| Pin 3 | IN- β Inverting input; connect to load side of shunt resistor |
| Pin 4 | IN+ β Non-inverting input; connect to supply side of shunt resistor |
| Pin 5 | V+ β Power supply, 2.7V to 40V, independent of common-mode voltage |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
INA139NA/3K-Q1 is suitable for 6 applications: Battery Charger Current Monitoring, Automotive Power Rail Monitoring, Server and Telecom DC Power Supplies, Overcurrent Protection and Fault Detection, Portable and Wearable Device Current Telemetry, Industrial 24V Control Panel Monitoring.
Battery Charger Current Monitoring
The INA139's 60uA quiescent current and 2.7V-40V common-mode range make it ideal for high-side charge-current sensing in 1S-10S lithium battery systems. Placed above the shunt on the charger input, its 440kHz bandwidth captures switching-ripple and transient charge currents, while the current-output architecture lets RL scale the signal directly into a charger MCU ADC range without a separate amplifier stage.
Recommended
Automotive Power Rail Monitoring
In 12V and 24V automotive buses, the INA139 monitors high-side load current for body control modules, infotainment, and e-call systems. The -40C to +125C temperature rating covers under-hood and passenger-compartment zones, and the 40V common-mode ceiling tolerates load-dump clamped transients on clamped rails. Its 60uA draw minimizes quiescent drain - critical for always-connected battery-current telemetry in vehicles parked for extended periods.
Recommended
Server and Telecom DC Power Supplies
Telecom -48V-derived and server 12V distribution rails need continuous current telemetry for power budgeting and fault detection. The INA139 measures shunt drop on the high side of these rails with its supply pin powered independently from a local 3.3V or 5V rail - a direct use of its independent supply/common-mode feature. The 440kHz bandwidth supports fast overcurrent comparator loops protecting hot-swap paths and DC-DC front ends.
Recommended
Overcurrent Protection and Fault Detection
Because the INA139 responds within microseconds across a 440kHz band, its output can drive a comparator directly for hardware overcurrent latching - faster than polled digital monitors. A shunt of 10-50mOhm and RL scaled for the comparator threshold create a simple, two-resistor protection circuit for motor drives, LED strings, and USB port protection, with the SOT-23-5 footprint occupying minimal board area near the protection point.
Recommended
Portable and Wearable Device Current Telemetry
In battery-powered portable devices, the INA139's 60uA consumption and 2.7V minimum supply let it monitor load current even during low-battery conditions. Engineers use the ground-referenced output to feed power-management ICs or fuel-gauge MCUs, profiling system sleep versus active current. The tiny SOT-23-5 package fits wearable and IoT PCBs where every square millimeter and every microamp of monitor overhead matters to runtime.
Recommended
Industrial 24V Control Panel Monitoring
Industrial PLC and control panels running 24V (nominal, up to 40V worst case) benefit from the INA139's common-mode ceiling for load-current supervision of actuators, solenoids, and sensor clusters. The analog output integrates easily with isolation amplifiers or ADC front ends, and the wide -40C to +125C range suits sealed cabinets without forced cooling. Single-resistor gain setting simplifies BOM standardization across multiple panel variants.
Recommended
Recommended Products Summary
Engineering reference data for INA139NA/3K-Q1 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | INA169NA/3K | INA139NA/250 | INA139AQDBVRQ1 |
|---|---|---|---|---|
| Package | SOT-23-5 (DBV) | SOT-23-5 (DBV) - same | SOT-23-5 (DBV) - same | SOT-23-5 (DBV) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Common-Mode Voltage Range | 2.7V to 40V | 2.7V to 60V | 2.7V to 40V | 2.7V to 40V |
| Bandwidth | 440 kHz | 440 kHz | 440 kHz | [DATA_NEEDED] |
| Quiescent Current | 60 uA (typ) | 60 uA (typ) | 60 uA (typ) | [DATA_NEEDED] |
| Output Type | Current output (via RL) | Current output (via RL) | Current output (via RL) | Current output (via RL) |
| Temperature Range | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C |
| Automotive Grade | AEC-Q1 suffix (verify Q1 documentation) | No (standard grade) | No (standard grade) | Yes (AEC-Q100, A-grade) |
| Reel Quantity | 3000 | 3000 | 250 | 3000 |
Key Differentiators
- Lowest-cost option within the TI current monitor family (vs INA240A1QPWRQ1)
- 40V common-mode headroom for 24V industrial rails (vs INA139NA/250)
- 60V upgrade path without redesign (vs INA169NA/3K)
Design Notes
Use Kelvin (4-wire) connections at the shunt resistor: route the IN+ and IN- traces directly from the shunt pads, not from shared power copper, or shunt trace resistance adds gain error. Keep the shunt drop in the 50-100mV range at full load to balance accuracy against power loss. Place the INA139 within a few millimeters of the shunt to minimize differential noise pickup on the high-impedance inputs.
The output is a current source into RL; choose RL so that VOUT = IS(max) x RL stays within the linear range (below roughly V+ - 1V, and within the ADC input range). Excessively large RL (above about 10k) reduces bandwidth and output compliance. Add a small capacitor across RL (100pF-1nF) to filter noise when feeding an ADC, accepting a bandwidth trade-off per the datasheet bandwidth equation.
The INA139 is unipolar: it cannot measure reverse (discharge vs charge direction) current - the output saturates at ground. If bidirectional sensing is needed, use INA240 or INA219 instead. Also remember common-mode and supply are independent but each must stay within 2.7V-40V; powering V+ below the shunt-side rail is allowed but do not let IN+/IN- fall below 2.7V during startup sequencing.
Compliance Information
RoHS compliance and lead-free status per TI product page for INA139NA/3K. The -Q1 suffix in the target MPN suggests automotive intent, but AEC-Q100 qualification was not confirmed in the provided web data - the verified TI page lists standard INA139NA/3K; verify Q1 documentation or use INA139AQDBVRQ1 for confirmed AEC-Q100.
