Texas Instruments INA205AIDR

Overview

INA205AIDR from Texas Instruments is a unidirectional current-shunt monitor IC with 100 V/V gain, dual open-drain comparators (CMP1 latched, CMP2 delay-programmable), and integrated 1.2-V reference output. It operates from 2.7 V to 18 V, supports –16 V to 80 V common-mode input range, and delivers 200 kHz bandwidth with ±2% total output error over –40°C to 125°C - used for overcurrent protection in telecom power supplies.

For engineers reviewing the INA205AIDR datasheet, INA205AIDR pinout, INA205AIDR application, or INA205AIDR equivalent, key selection factors include its 100 V/V fixed gain, 1.2-V REF OUT capability, comparator hysteresis (±8 mV), 1.3-μs typical response time, and SOIC-14 package compatibility with high-side shunt monitoring at up to 80 V common-mode.

Technical Context

The INA205AIDR implements a precision current-sense amplifier stage followed by two independent comparators: CMP1 features internal latch and active-low reset (CMP1 RESET), while CMP2 accepts an external capacitor on CMP2 DELAY to set programmable delay (e.g., 0.1 μF = 0.5 s). Both comparators use internal 0.6-V references, overrideable on pins 3 and 6 in 14-pin packages.

Its architecture supports unidirectional sensing only, with RTI offset voltage ≤±3.5 mV over temperature and CMRR ≥100 dB at 12 V common-mode. The 1.2-V reference (±12 mV accuracy, 40–100 ppm/°C drift) is buffered and capable of sourcing/sinking up to 1 mA, enabling biasing of external circuitry without added components.

Key Specifications

Pinout & Package

INA205AIDR is housed in a 14-pin SOIC (D) package (8.65 mm × 3.91 mm), RoHS-compliant, with standard 1.27-mm pitch and exposed pad not present. Thermal resistance R_θJA = 84.9°C/W enables operation at full spec without forced airflow in compact PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current-shunt monitor applications.

Compared with INA204AIDR and INA206AIDR, the INA205AIDR uniquely combines 100 V/V gain, dual comparators with latching and programmable delay, and a buffered 1.2-V reference - making it optimal for high-precision, high-reliability unidirectional overcurrent protection where space and component count are constrained.

Availability

INA205AIDR is available at Aetrix Electronics and suitable for telecom power supplies, automotive battery management, industrial motor drives, and welding equipment requiring stable component supply across extended temperature and voltage ranges.

Supply support for INA205AIDR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision signal conditioning and power management ICs.

The INA20x family was designed specifically for high-voltage unidirectional current sensing in power conversion systems - integrating amplification, comparison, and reference functions into a single package to simplify overcurrent protection design.

FAQ

What is the maximum common-mode voltage the INA205AIDR can handle?

The INA205AIDR supports a common-mode input range from –16 V to +80 V. This allows direct high-side shunt connection in 48-V telecom systems or industrial 24/48-V DC distribution without level-shifting circuitry. Operation at 80 V requires adherence to absolute maximum ratings - VIN+ and VIN− must not exceed VS + 0.3 V or go below GND – 0.3 V.

Does the INA205AIDR support bidirectional current sensing?

No, the INA205AIDR is strictly a unidirectional current-shunt monitor. Its internal architecture measures only positive differential voltage (VIN+ > VIN−) and cannot resolve reverse current flow. For bidirectional applications, TI's INA206AIDR or INA271AIDR are appropriate alternatives - neither shares pin compatibility or functional equivalence with the INA205AIDR.

How is the comparator delay set on the INA205AIDR?

The comparator 2 delay on the INA205AIDR is set by connecting an external capacitor between the CMP2 DELAY pin and GND. The delay time (t_D) in seconds equals 5 × C_DELAY in microfarads - for example, a 0.1-μF capacitor yields ~0.5 s delay. Capacitor values from 0.01 μF to 1 μF are supported, enabling delays from 50 ms to 5 s.

Can the 1.2-V reference output of the INA205AIDR be used to bias external circuitry?

Yes, the 1.2-V REF OUT pin provides a buffered, low-drift reference capable of sourcing or sinking up to 1 mA. It is specified at ±12 mV accuracy over temperature and exhibits 40–100 ppm/°C drift. For optimal stability, connect a 0.1-μF ceramic capacitor from 1.2-V REF OUT to GND near the device.

What is the purpose of the CMP1 RESET pin on the INA205AIDR?

The CMP1 RESET pin is an active-low input that clears the latched state of Comparator 1. When pulled low for ≥1.5 μs, it releases the CMP1 OUT signal. If left open or grounded, CMP1 operates in transparent mode (non-latching). This pin enables manual or microcontroller-driven fault acknowledgment - critical for systems requiring operator confirmation before resuming operation after overcurrent events.