Choose your country or region.

EnglishFrançaispolskiSlovenija한국의DeutschSvenskaSlovenskáMagyarországItaliaहिंदीрусскийTiếng ViệtSuomiespañolKongeriketPortuguêsภาษาไทยБългарски езикromânescČeštinaGaeilgeעִבְרִיתالعربيةPilipinoDanskMelayuIndonesiaHrvatskaفارسیNederlandTürk diliΕλλάδαRepublika e ShqipërisëአማርኛAzərbaycanEesti VabariikEuskeraБеларусьíslenskaBosnaAfrikaansIsiXhosaisiZuluCambodiaსაქართველოҚазақшаAyitiHausaКыргыз тилиGalegoCatalàCorsaKurdîLatviešuພາສາລາວlietuviųLëtzebuergeschmalaɡasʲМакедонскиMaoriМонголулсবাংলা ভাষারမြန်မာनेपालीپښتوChicheŵaCрпскиSesothoසිංහලKiswahiliТоҷикӣاردوУкраїнаO'zbekગુજરાતીಕನ್ನಡkannaḍaதமிழ் மொழி繁体中文
Home > Products > Integrated Circuits (ICs) > Power Management (PMIC) - Current Regulation/Management > INA138NA/3K
296~4073253-4~DBV~5.jpg ImageView larger image
Image may be representation.
See specs for product details.

INA138NA/3K

In Stock 15800 pcs Reference Price(In US Dollars)
1+
$3.2829
Manufacturer Part Number:
INA138NA/3K
Manufacturer / Brand
Texas Instruments
Part of Description:
IC CURRENT MONITOR 0.5% SOT23-5
Datasheets:
INA138NA/3K(1).pdfINA138NA/3K(2).pdfINA138NA/3K(3).pdf
Lead Free Status / RoHS Status:
ROHS3 Compliant
Stock Condition:
New original, 15800 pcs Stock Available.
ECAD Model:
Ship From:
Hong Kong
Shipment Way:
DHL/Fedex/TNT/UPS

Inquiry Online

Please complete all required fields with your contact information.Click "SUBMIT REQUEST" we will contact you shortly by email. Or Email us: Info@IC-Components.com
Part Number
Manufacturer
Require Quantity
Target Price(USD)
Company Name
Contact Name
E-mail
Phone
Message
Please enter Verify Code and click "Submit"
Part Number INA138NA/3K
Manufacturer / Brand Texas Instruments
Stock Quantity 15800 pcs Stock
Category Integrated Circuits (ICs) > Power Management (PMIC) - Current Regulation/Management
Description IC CURRENT MONITOR 0.5% SOT23-5
Lead Free Status / RoHS Status: ROHS3 Compliant
RFQ INA138NA/3K Datasheets INA138NA/3K Details PDF
INA138NA/3K Details PDF for FR.pdf
INA138NA/3K Details PDF for KR.pdf
INA138NA/3K Details PDF for IT.pdf
INA138NA/3K Details PDF for DE.pdf
INA138NA/3K Details PDF for ES.pdf
Voltage - Input 2.7V ~ 36V
Supplier Device Package SOT-23-5
Series -
Sensing Method High-Side
Package / Case SC-74A, SOT-753
Package Tape & Reel (TR)
Operating Temperature -40°C ~ 125°C
Mounting Type Surface Mount
Function Current Monitor
Current - Output -
Base Product Number INA138
Accuracy ±0.5%

Packaging & ESD

Industry-standard static shielding packaging is used for electronic components.Anti-static, light-transparent materials allow easy identification of ICs and PCB assemblies.
The packaging structure provides electrostatic protection based on Faraday cage principles.This helps protect sensitive components from static discharge during handling and transportation.


All products are packed in ESD-safe anti-static packaging. Outer packaging labels include part number, brand, and quantity for clear identification. Goods are inspected prior to shipment to ensure proper condition and authenticity.

ESD protection is maintained throughout packing, handling, and global transportation. Secure packaging provides reliable sealing and resistance during transit. Additional cushioning materials are applied when required to protect sensitive components.

QC(Part Testing by IC Components)Quality Warranty

We can offer worldwide express delivery service, such as DHLor FedEx or TNT or UPS or other forwarder for shipment.

Global Shipment by DHL/FedEx/TNT/UPS

Shipping Fees reference DHL/FedEx
1). You can offer your express delivery account for shipment, ifyou haven’t any express account for shipment, we can offer our account inadvance.
2). Use our account for shipment, Shipment charges(Reference DHL/FedEx, Different Countries has different price.)
Shipment charges： (Reference DHL and FedEX)
Weight(KG): 0.00kg-1.00kg Price(USD$) : USD$60.00
Weight(KG): 1.00kg-2.00kg Price(USD$) : USD$80.00
* The price of cost is reference with DHL/FedEx. The detail charges, please contact us. Different country the express charges are different.



We accept the payment terms: Telegraphic Transfer(T/T), Credit Card, PayPal and Western Union.

PayPal:

PayPal Bank Information:
Company Name : IC COMPONENTS LTD
Paypal ID: PayPal@IC-Components.com

BANK TRANSFAR (Telegraphic Transfer)

Payment For Telegraphic Transfers:
Company Name : IC COMPONENTS LTD Beneficiary Account Number : 549-100669-701
Beneficiary Bank name : Bank of Communications (Hong Kong) Ltd Beneficiary Bank Code : 382 (for local payment)
Beneficiary Bank SWIFT : COMMHKHK
Beneficiary Bank Address : Tsuen Wan Market Street Branch 53 Market Street, Tsuen Wan N.T., Hong Kong

Any inquires or questions, please kindly contact us Email: Info@IC-Components.com


INA138NA/3K Product Details:

The INA138NA/3K is a high-performance current monitoring integrated circuit designed by Texas Instruments, specifically engineered for precise current measurement and management in electronic systems. This compact surface-mount device offers exceptional functionality as a high-side current monitor, enabling accurate current sensing across a wide input voltage range of 2.7V to 36V.

Featuring a sophisticated SOT-23-5 compact package, this IC addresses critical design challenges in current measurement by providing remarkable accuracy of ±0.5%. Its robust operating temperature range from -40°C to 125°C ensures reliable performance across diverse environmental conditions, making it suitable for demanding industrial and automotive applications.

The current monitor's key advantages include its lead-free and RoHS-compliant construction, which supports modern environmental standards, and its high-side sensing capability that allows for precise current measurement without disrupting circuit ground references. Its small form factor and surface-mount design facilitate easy integration into compact electronic systems.

Potential application areas include power management systems, battery monitoring, motor control circuits, telecommunications equipment, and automotive electronics where precise current measurement is crucial. The device's high input voltage tolerance and exceptional accuracy make it particularly valuable in scenarios requiring reliable current sensing.

Equivalent or alternative models in the same product family include:

- INA138NA

- INA138A

- INA138U

- Similar Texas Instruments current monitoring ICs in the INA138 series

This versatile current monitor represents an advanced solution for engineers seeking high-precision current measurement with minimal circuit complexity and maximum reliability.

INA138NA/3K Image
INA138NA/3K (1)

INA138NA/3K Key Technical Attributes

Manufacturer Part Number: INA138NA/3K

Manufacturer: Luminary Micro / Texas Instruments

Main Category: Integrated Circuits (ICs)

Small Classification: PMIC - Current Regulation/Management

INA138NA/3K Packing Size

Package Type: SOT-23-5

Material: Cut Tape (CT)

Dimensions: SC-74A, SOT-753

Pin Configuration: 5 pins

Thermal Characteristics: Moisture Sensitivity Level (MSL) 2 (1 Year)

Electrical Properties: Voltage - Input: 2.7 V ~ 36 V

INA138NA/3K Application

High-Side Current Monitoring

Suitable for power management applications requiring precise current regulation and management

INA138NA/3K Features

The INA138NA/3K from Texas Instruments is specifically designed for high-side current monitoring, making it exceptionally suitable for applications where power supply monitoring is crucial. It supports a wide input voltage range from 2.7V to 36V, which allows flexibility across various types of circuit designs. Additionally, it features a very accurate sensing ability with an accuracy of ±0.5%, which ensures reliable performance in critical applications. The device operates over an extensive temperature range from -40°C to 125°C, making it robust for challenging environmental conditions.

INA138NA/3K Quality and Safety Features

RoHS compliant indicating the device is lead-free and adheres to EU standards for environmental protection and safety. The device features a robust design capable of handling moisture sensitivity up to Level 2 for a year, ensuring long-term reliability.

INA138NA/3K Compatibility

This device is compatible with surface mount technology and is mainly utilized in configurations where high-side current measurement is required within integrated circuits setups. It fits into a wide variety of electronic circuit architectures due to its versatile voltage input range and compact SOT-23-5 package.

INA138NA/3K Datasheet PDF

For the most accurate and comprehensive information including detailed specifications, application guidance, and more, the datasheet for the INA138NA/3K is available for download on our website. We endorse customers to access this authoritative datasheet to ensure successful integration and utilization of the component in their projects.

Quality Distributor

IC-Components is a premium distributor for Luminary Micro / Texas Instruments products, including the INA138NA/3K. AT IC-Components, we commit to providing top quality parts and the best customer service. We encourage customers to get quotes and place orders via our website to guarantee the best deals and assured product authenticity.

Frequently Asked Questions

What are the key design constraints when integrating the INA138NA/3K into a high-side current sensing application with a 24V industrial bus?
When using the INA138NA/3K in a 24V industrial high-side current sensing setup, ensure that the common-mode voltage remains within the 2.7V to 36V input range. The device’s ±0.5% accuracy is achievable only if the sense resistor is placed between the supply rail and the load (high-side configuration), and the differential voltage across the sense resistor does not exceed 500mV. Additionally, pay attention to PCB layout: minimize trace resistance and thermal gradients near the sense resistor to avoid offset errors. The INA138NA/3K’s open-collector output requires an external pull-up resistor, which must be sized based on the desired response time and load capacitance to prevent signal integrity issues in noisy industrial environments.
Can the INA138NA/3K be used for bidirectional current monitoring, or is it limited to unidirectional sensing?
The INA138NA/3K is strictly a unidirectional current monitor. Its internal architecture assumes current flows from the high-side supply through the sense resistor into the load. It cannot detect reverse current flow because the output stage is an open-collector comparator that only pulls low when the sensed voltage exceeds the internal 50mV threshold. For bidirectional applications, consider alternatives like the INA240 or INA228, which support true bidirectional sensing with appropriate reference biasing—using the INA138NA/3K in such a scenario would result in missed fault conditions or incorrect readings.
What are the risks of replacing a MAX4080 with the INA138NA/3K in an existing motor control design?
Replacing the MAX4080 with the INA138NA/3K introduces several critical differences: the MAX4080 provides a buffered, ratiometric output proportional to current, while the INA138NA/3K is a comparator-based regulator with a digital open-collector output that only indicates whether current exceeds a threshold. This means you lose analog current magnitude information unless you redesign the feedback loop. Additionally, the MAX4080 has built-in gain (e.g., 20V/V), whereas the INA138NA/3K requires external gain setting via the sense resistor and pull-up network. Migration is not drop-in and requires significant firmware and hardware changes to maintain system functionality.
How does the open-collector output of the INA138NA/3K affect interfacing with a 3.3V microcontroller in a low-power design?
The open-collector output of the INA138NA/3K allows flexible interfacing with a 3.3V microcontroller by connecting the pull-up resistor to the MCU’s VDD (3.3V). However, ensure the pull-up value balances speed and power: a 10kΩ resistor limits quiescent current but may slow rise time under heavy capacitive loading. For low-power designs, avoid very low resistor values (<4.7kΩ) to minimize static current draw. Also, verify that the INA138NA/3K’s output can sink sufficient current (up to 16mA typical) to meet the MCU’s input low-level voltage specification under all operating temperatures, especially at -40°C where leakage characteristics may shift.
Is the INA138NA/3K suitable for battery-powered IoT devices requiring ultra-low standby current?
The INA138NA/3K is not ideal for ultra-low-power IoT applications due to its typical quiescent current of 12µA (plus additional current through the sense resistor and pull-up). While 12µA is relatively low, it becomes significant in multi-year battery life designs. Furthermore, the device lacks a shutdown or enable pin, so power cycling requires external switching. For such use cases, consider zero-drift, low-IQ alternatives like the INA219 or LTC2947, which offer integrated ADCs and lower overall system power. The INA138NA/3K is better suited for always-on industrial monitoring where power budget is less constrained.
What layout practices are critical to maintain ±0.5% accuracy when using the INA138NA/3K in a high-noise environment?
To preserve the INA138NA/3K’s ±0.5% accuracy in electrically noisy settings, implement a Kelvin connection for the sense resistor to eliminate errors from trace resistance. Place the sense resistor as close as possible to the INA138NA/3K’s IN+ and IN− pins, and route these traces differentially with matched lengths and spacing. Use a ground plane beneath the device but avoid running high-current return paths under the sense circuitry. Add a small RC filter (e.g., 10Ω + 1nF) at the output to suppress high-frequency noise without significantly degrading response time. Thermal symmetry around the sense resistor is also essential—avoid placing heat-generating components nearby to prevent thermoelectric offset drift.
Can the INA138NA/3K operate reliably in an automotive under-hood application with ambient temperatures reaching 125°C?
Yes, the INA138NA/3K is rated for operation from -40°C to 125°C, making it suitable for automotive under-hood environments. However, ensure that the entire signal chain—including the sense resistor and pull-up components—is also rated for 125°C continuous operation. Derate power dissipation in the sense resistor to avoid thermal runaway, and verify long-term stability of solder joints and PCB materials under thermal cycling. The SOT-23-5 package has limited thermal mass, so avoid localized heating from adjacent components. Additionally, confirm compliance with AEC-Q100 if required; while the INA138NA/3K is industrial-grade, it is not officially automotive-qualified unless specified by Texas Instruments under a separate part number.
What happens if the common-mode voltage drops below 2.7V while using the INA138NA/3K in a 3.3V system?
If the common-mode voltage falls below the minimum 2.7V specification—such as during brownout conditions in a 3.3V system—the INA138NA/3K may fail to regulate properly, leading to unpredictable output behavior or complete loss of current monitoring function. The internal reference and comparator circuits require this minimum headroom to operate. In such cases, consider adding a supervisory circuit to disable downstream logic or switch to a backup power source. Alternatively, select a low-voltage current monitor like the INA199, which supports common-mode voltages down to –0.3V, ensuring continued operation during transient dips.
How do I set the current threshold accurately when using the INA138NA/3K with a precision sense resistor?
The current threshold in the INA138NA/3K is determined by the internal 50mV reference divided across the sense resistor: I_threshold = 50mV / R_sense. To achieve high accuracy, use a precision sense resistor (≤0.1% tolerance, low TCR) and account for the ±0.5% accuracy specification of the INA138NA/3K itself. Calibrate the system during production if tighter thresholds are needed. Note that the open-collector output only indicates threshold crossing—it does not provide proportional current data—so analog feedback loops must rely on external circuitry. Always validate threshold behavior across the full temperature range, as both the reference and resistor drift with temperature.
Are there pin-compatible alternatives to the INA138NA/3K that offer enhanced features like built-in gain or I²C output?
The INA138NA/3K in SOT-23-5 (SC-74A) has limited pin-compatible drop-in replacements with enhanced features due to its simple 5-pin comparator-based architecture. However, for designs needing digital output or programmable thresholds, consider migrating to devices like the INA226 (I²C interface, integrated shunt monitor) or INA301 (comparator with adjustable threshold via external resistor), though these require different footprints and supply configurations. There is no direct functional or pin-compatible upgrade within the same package that adds gain or communication—any migration will involve schematic and layout changes. Always re-evaluate system requirements before substituting, as the INA138NA/3K’s simplicity is its strength in cost-sensitive, threshold-detection applications.

Recent Reviews

Leave Comment
Hello, you have not logged in, please log in
User Login

Forgot password?

No account yet? Register now

Tips
Please speak legally
Your email will be hidden
Please complete all required fields ( denoted with* )
Mark
5.0

You May Also Be Interested In:


INA138NA/3K

INA138NA/3K

Texas Instruments

IC CURRENT MONITOR 0.5% SOT23-5

In Stock: 15800

SUBMIT RFQ