Texas Instruments INA303A3IPWR

Overview

INA303A3IPWR from Texas Instruments is a 36-V, precision current-sense amplifier with dual integrated comparators configured as a window comparator for simultaneous overcurrent and undercurrent detection. It features 100 V/V gain, ±30 µV max offset voltage, 0.15% max gain error, and operates from 2.7 V to 5.5 V supply - used in motor control and power-supply protection circuits where bidirectional current monitoring and fast fault response are critical.

For engineers reviewing the INA303A3IPWR datasheet, INA303A3IPWR pinout, INA303A3IPWR application, or INA303A3IPWR equivalent, this page delivers verified electrical specifications, TSSOP-14 pin functions, window-comparator timing behavior, and real-world implementation context for high-reliability current monitoring in industrial and computing systems.

Technical Context

The INA303A3IPWR integrates a zero-drift, bidirectional current-sense amplifier with two independent comparators: COMP1 triggers on overcurrent (ALERT1), while COMP2 implements a user-configurable window comparator using LIMIT1 (overlimit) and LIMIT2 (underlimit) inputs. Its –0.1 V to +36 V common-mode input range enables direct sensing on high-side or low-side shunts independent of VS.

Comparator 1 delivers sub-1 µs propagation delay with fixed response; Comparator 2 supports adjustable delay (2 µs to 10 s) via external CDELAY and DELAY pin current (5 µA typ), enabling precise fault-hold timing. Both open-drain ALERT outputs support latched or transparent mode via dedicated LATCH1/LATCH2 digital inputs.

Key Specifications

Pinout & Package

The INA303A3IPWR is housed in a 14-pin TSSOP package (4.40 mm × 5.00 mm), optimized for thermal performance (R_θJA = 110.2°C/W) and PCB space efficiency in high-density power systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current-sense amplifier with integrated comparator applications.

Compared with INA302A3IPWR, the INA303A3IPWR adds undercurrent detection via LIMIT2, enabling true window-based fault classification; compared with INA240A3IPW, it integrates comparators with sub-1 µs response and programmable delay, reducing design complexity and improving system-level fault response determinism.

Availability

INA303A3IPWR is available at Aetrix Electronics and suitable for motor control, server power-supply protection, and industrial PLC analog input modules requiring stable component supply and long-term production continuity.

Supply support for INA303A3IPWR 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 INA30x product line was designed specifically for high-reliability current monitoring in industrial, computing, and telecom infrastructure - integrating precision amplification with intelligent, configurable fault detection in a single compact package.

FAQ

What is the maximum common-mode voltage the INA303A3IPWR can handle?

The INA303A3IPWR supports a common-mode input voltage range of –0.1 V to +36 V, independent of its 2.7 V to 5.5 V supply voltage. This allows direct connection to high-voltage rails such as 24-V or 36-V motor drives or telecom rectifiers without external level-shifting circuitry. The specification is guaranteed across the full operating temperature range (–40°C to +125°C), making INA303A3IPWR suitable for demanding industrial environments where bus voltages exceed logic supply levels.

How does the window comparator function in the INA303A3IPWR differ from the INA302A3IPWR?

The INA303A3IPWR implements a true window comparator: LIMIT1 sets the upper (overcurrent) threshold and LIMIT2 sets the lower (undercurrent) threshold, enabling detection of both excessive and insufficient current. In contrast, the INA302A3IPWR configures both comparators for overcurrent-only detection. This makes INA303A3IPWR essential for applications like open-load detection in solenoids or reverse-current monitoring in battery backup systems - functions not supported by INA302A3IPWR.

Can the ALERT2 delay time be adjusted, and what is the range?

Yes, the ALERT2 delay time in the INA303A3IPWR is set by an external capacitor (CDELAY) connected to the DELAY pin and is programmable from 2 µs to 10 s. The delay is generated by charging CDELAY with a precision 5 µA current source; the resulting voltage ramp crosses a 1.22 V internal threshold to trigger the alert. This allows designers to reject short-duration inrush currents (e.g., motor startup) while maintaining fast response to sustained faults - a capability not available on ALERT1, which has a fixed sub-1 µs propagation delay.

What is the purpose of the REF pin on the INA303A3IPWR?

The REF pin on the INA303A3IPWR sets the output voltage midpoint for bidirectional current sensing. When a reference voltage (e.g., 2.5 V) is applied to REF, the OUT pin outputs VREF ± (I_LOAD × R_SENSE × Gain), enabling measurement of both positive (supply-to-load) and negative (load-to-supply) current flow. This eliminates the need for dual-supply op-amps or level-shifting circuitry, simplifying design in single-supply systems such as 3.3-V microcontrollers interfacing with 24-V motor drivers.

Does the INA303A3IPWR support latched or transparent alert modes, and how are they controlled?

Yes, the INA303A3IPWR supports both latched and transparent alert modes independently for each comparator output. LATCH1 controls ALERT1 behavior, and LATCH2 controls ALERT2 behavior: driving the respective pin low enables latched mode (alert remains active until manually cleared), while driving it high enables transparent mode (alert follows real-time comparator state). This flexibility allows system designers to implement different fault-handling strategies - for example, latching overcurrent faults while keeping undercurrent alerts transparent for continuous monitoring.