INA138

ACTIVE

2.7 to 36V, 800kHz Variable gain current sense amplifier

Product details

Product type Analog output Common-mode voltage (max) (V) 36 Common-mode voltage (min) (V) 2.7 Input offset (±) (max) (µV) 1000 Input offset drift (±) (typ) (µV/°C) 1 Features Current Output Rating Catalog Voltage gain (V/V) adjustable CMRR (min) (dB) 100 Bandwidth (kHz) 32 Iq (max) (mA) 0.06 Number of channels 1 Comparators (#) 0 Gain error (%) 2 Gain error drift (±) (max) (ppm/°C) 100 Operating temperature range (°C) -40 to 125
Product type Analog output Common-mode voltage (max) (V) 36 Common-mode voltage (min) (V) 2.7 Input offset (±) (max) (µV) 1000 Input offset drift (±) (typ) (µV/°C) 1 Features Current Output Rating Catalog Voltage gain (V/V) adjustable CMRR (min) (dB) 100 Bandwidth (kHz) 32 Iq (max) (mA) 0.06 Number of channels 1 Comparators (#) 0 Gain error (%) 2 Gain error drift (±) (max) (ppm/°C) 100 Operating temperature range (°C) -40 to 125
SOT-23 (DBV) 5 8.12 mm² (2.9 mm × 2.8 mm)
  • Complete Unipolar High-Side Current Measurement Circuit
  • Wide Supply and Common-Mode Range
  • INA138: 2.7 V to 36 V
  • INA168: 2.7 V to 60 V
  • Independent Supply and Input Common-Mode Voltages
  • Single Resistor Gain Set
  • Low Quiescent Current (25 µA Typical)
  • Wide Temperature Range: –40°C to +125°C
  • 5-Pin SOT-23 Package
  • Complete Unipolar High-Side Current Measurement Circuit
  • Wide Supply and Common-Mode Range
  • INA138: 2.7 V to 36 V
  • INA168: 2.7 V to 60 V
  • Independent Supply and Input Common-Mode Voltages
  • Single Resistor Gain Set
  • Low Quiescent Current (25 µA Typical)
  • Wide Temperature Range: –40°C to +125°C
  • 5-Pin SOT-23 Package

The INA138 and INA168 (INA1x8) are high-side, unipolar, current shunt monitors. Wide input common-mode voltage range, low quiescent current, and tiny SOT-23 packaging enable use in a variety of applications.

Input common-mode and power-supply voltages are independent and can range from 2.7 V to 36 V for the INA138 and 2.7 V to 60 V for the INA168. Quiescent current is only 25 µA, which permits connecting the power supply to either side of the current measurement shunt with minimal error.

The device converts a differential input voltage to a current output. This current is converted back to a voltage with an external load resistor that sets any gain from 1 to over 100. Although designed for current shunt measurement, the circuit invites creative applications in measurement and level shifting.

Both the INA138 and INA168 are available in SOT23-5 and are specified for the –40°C to 125°C temperature range.

 

The INA138 and INA168 (INA1x8) are high-side, unipolar, current shunt monitors. Wide input common-mode voltage range, low quiescent current, and tiny SOT-23 packaging enable use in a variety of applications.

Input common-mode and power-supply voltages are independent and can range from 2.7 V to 36 V for the INA138 and 2.7 V to 60 V for the INA168. Quiescent current is only 25 µA, which permits connecting the power supply to either side of the current measurement shunt with minimal error.

The device converts a differential input voltage to a current output. This current is converted back to a voltage with an external load resistor that sets any gain from 1 to over 100. Although designed for current shunt measurement, the circuit invites creative applications in measurement and level shifting.

Both the INA138 and INA168 are available in SOT23-5 and are specified for the –40°C to 125°C temperature range.

 

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Technical documentation

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Simulation model

INA138 PSpice Model (Rev. A)

SBOM140A.ZIP (25 KB) - PSpice model
Supported products & hardware
Simulation model

INA138 TINA-TI Reference Design (Rev. A)

SBOC152 (14 KB) - TINA-TI reference design
Supported products & hardware
Simulation model

INA138 TINA-TI Spice Model

SBFC024.TSM (3 KB) - TINA-TI Spice model
Supported products & hardware
Calculation tool

ANALOG-ENGINEER-CALC — PC software analog engineer's calculator

The analog engineer’s calculator is designed to speed up many of the repetitive calculations that analog circuit design engineers use on a regular basis. This PC-based tool provides a graphical interface with a list of various common calculations ranging from setting operational-amplifier (...)

Supported products & hardware
Calculation tool

CS-AMPLIFIER-ERROR-TOOL — Current Sense Amplifier Comparison and Error Tool

This Excel calculator provides a comparison between two and five of our standard current sense amplifiers, delivering a chart containing the basic parameters of each device. This calculator also takes system condition inputs from users such as common-mode voltage, supply voltage, shunt resistor (...)
Supported products & hardware
Design tool

CIRCUIT060032 — High-voltage, high-side floating current sensing circuit using current output, current sense amp

This cookbook is intended to demonstrate a method of designing an accurate current sensing solution for systems with high common mode voltages. The principle aspect of this design uses a unidirectional circuit to monitor a system with Vcm = 400V by floating the supplies of the device across a (...)
Supported products & hardware
Design tool

SGLC001 — Source Files for SBOA295

Supported products & hardware
Reference design

TIDA-00332 — High Voltage 12 V – 400 V DC Current Sense Reference Design

This Verified Design shows a circuit to measure currents with a common mode of up to 400V using an INA138. This is achieved by creating a simple floating power supply and biasing the INA138 directly from the high voltage source. The 400V in this design is an example. With different components even (...)

Supported products & hardware
Reference design

TIDA-00799 — Quad-Channel, 12-Bit, 50-MSPS ADC Reference Design With Low Noise, Low Distortion, DC and AC Inputs

This reference design demonstrates how to implement a single-ended-to-differential input path, which can be AC-coupled or DC-coupled for an ADC3422. It also explains how to design a high-input impedance, DC-coupled input path. The reference design can be used for applications such as low-power (...)
Supported products & hardware
Package Pins CAD symbols, footprints & 3D models
SOT-23 (DBV) 5 Ultra Librarian

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