Texas Instruments INA310B1QDGKRQ1

Overview

INA310B1QDGKRQ1 from Texas Instruments is an AEC-Q100 Grade 1 (−40°C to +125°C) ultra-precise current sense amplifier with integrated open-drain comparator and 0.6 V internal reference, designed for high-side or low-side shunt monitoring in automotive power systems. It delivers 20 V/V fixed gain, −4 V to +110 V common-mode input range, 1.3 MHz bandwidth, and ±150 µV max offset voltage - enabling accurate, fast overcurrent detection in eTurbo, EPS, and regenerative braking circuits.

For engineers reviewing the INA310B1QDGKRQ1 datasheet, INA310B1QDGKRQ1 pinout, INA310B1QDGKRQ1 application, or INA310B1QDGKRQ1 equivalent, key selection criteria include its wide common-mode operation independent of supply voltage, latching comparator mode via RESET pin, 1 µs propagation delay, and VSSOP-8 packaging optimized for space-constrained automotive PCB layouts.

Technical Context

The INA310B1QDGKRQ1 employs a zero-drift precision amplifier topology with matched internal resistor network to achieve 0.5% max gain error and ±1 µV/°C offset drift across −40°C to +125°C. Its input stage supports differential sensing up to ±12 V while rejecting common-mode voltages from −4 V to +110 V - decoupled from the 2.7 V to 20 V supply rail.

The integrated comparator uses a stable 0.6 V internal reference with 8 mV hysteresis and operates with transparent or latched behavior controlled by the RESET pin (active-high latch enable). Propagation delay remains ≤1 µs under 20 mV overdrive, and CMPOUT is open-drain, supporting pull-up to up to 20 V independent of VS.

Key Specifications

Pinout & Package

VSSOP-8 package (3.00 mm × 4.90 mm), thermally enhanced for automotive under-hood environments; 0.65 mm pitch, exposed thermal pad optional per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current sense amplifier applications.

Compared with INA240A1QDRQ1 and MAX40056ATA+T, the INA310B1QDGKRQ1 uniquely combines AEC-Q100 Grade 1 qualification, −4 V to +110 V common-mode operation, integrated comparator with latching mode, and 1.3 MHz bandwidth - making it the only option qualified for safety-critical, high-voltage automotive current monitoring with autonomous fault response.

Availability

INA310B1QDGKRQ1 is available at Aetrix Electronics and suitable for electric power steering (EPS), starter/generator, and regenerative braking systems requiring stable component supply, long-term automotive lifecycle support, and traceable AEC-Q100-compliant sourcing.

Supply support for INA310B1QDGKRQ1 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 deep expertise in automotive-grade signal conditioning and power management ICs.

The INA310x-Q1 product line was engineered specifically for high-reliability automotive current sensing - addressing the need for precision, speed, and functional safety in next-generation 48 V mild-hybrid, xEV traction, and ADAS power systems.

FAQ

What is the maximum common-mode voltage the INA310B1QDGKRQ1 can withstand during normal operation?

The INA310B1QDGKRQ1 supports a continuous common-mode input range of −4 V to +110 V during normal operation. This range is independent of the supply voltage (2.7 V to 20 V), enabling reliable high-side sensing above battery rail in 48 V systems. Its survival rating extends to −20 V to +120 V, covering automotive load-dump and reverse-battery transients without damage.

How does the RESET pin affect comparator behavior in the INA310B1QDGKRQ1?

The RESET pin on the INA310B1QDGKRQ1 controls comparator latching mode: when held high, the comparator output (CMPOUT) latches high upon overcurrent detection and remains asserted until RESET is pulled low or left floating; when grounded or open, the comparator operates in transparent mode, tracking CMPIN continuously. This dual-mode flexibility supports both diagnostic logging and immediate hardware fault shutdown in the same design.

Can the INA310B1QDGKRQ1 be used with a 3.3 V microcontroller for comparator interfacing?

Yes - the CMPOUT pin is open-drain and rated for up to 20 V pull-up, so it can be safely interfaced with a 3.3 V microcontroller by using a pull-up resistor to 3.3 V. The RESET pin also accepts 3.3 V logic levels (VIH min = 1.2 V, VIL max = 0.4 V), and the analog OUT pin swings down to GND + 5 mV, ensuring compatibility with 3.3 V ADC references.

What is the typical propagation delay of the INA310B1QDGKRQ1 comparator under 20 mV overdrive?

The INA310B1QDGKRQ1 comparator exhibits a typical small-signal propagation delay of 1 µs when the input overdrive is 20 mV - measured from the moment CMPIN crosses the 0.6 V threshold to CMPOUT transition. This value is guaranteed across −40°C to +125°C and forms the basis for its use in fast overcurrent protection schemes where sub-2 µs response is mandatory.

Does the INA310B1QDGKRQ1 require external components to set the overcurrent threshold?

Yes - the overcurrent threshold is set externally using a resistive divider from OUT to GND, feeding into CMPIN. The internal 0.6 V reference defines the trip point, so R1/(R1+R2) × V_OUT = 0.6 V determines the sensed current limit. TI recommends keeping the total divider resistance below 100 kΩ to minimize error from comparator input bias current (<20 nA near threshold).