Texas Instruments OPA348AIDRG4

Overview

OPA348AIDRG4 from Texas Instruments is a single-channel, rail-to-rail input/output CMOS operational amplifier optimized for low-power, single-supply applications. It delivers 1 MHz gain-bandwidth, 45 µA quiescent current, and 0.5 pA input bias current, operating from 2.1 V to 5.5 V. It serves as an ADC input driver in portable sensor interfaces-e.g., smoke alarms and CO detectors-where high-impedance signal conditioning and battery longevity are critical.

For engineers reviewing the OPA348AIDRG4 datasheet, OPA348AIDRG4 pinout, OPA348AIDRG4 application, or OPA348AIDRG4 equivalent, key selection criteria include its rail-to-rail input range extending 200 mV beyond supply rails, 18 mV output swing from rail (RL = 100 kΩ), and guaranteed operation across –40°C to +125°C for industrial and safety-critical embedded systems.

Technical Context

The OPA348AIDRG4 employs a complementary N/P-channel input stage enabling true rail-to-rail common-mode operation from (V–) – 0.2 V to (V+) + 0.2 V. Its unity-gain stable architecture supports direct driving of capacitive loads up to 250 pF without external compensation.

It features a folded-cascode gain stage with class AB output, delivering 0.5 V/µs slew rate and 5 µs 0.1% settling time (2-V step, CL = 100 pF). Input offset voltage is specified at 1–5 mV (typ/max), with drift of 4 µV/°C over temperature.

Key Specifications

Pinout & Package

OPA348AIDRG4 is packaged in an 8-pin SOIC (D package), 4.90 mm × 3.91 mm body size, with standard surface-mount footprint and thermal performance (R_θJA = 142°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA333AIDBVR and MCP6001T-I/OT, OPA348AIDRG4 uniquely balances ultra-low quiescent current (45 µA), rail-to-rail I/O, and full industrial temperature range - making it the optimal choice for safety-critical, battery-constrained sensor nodes where parametric stability across temperature and time is non-negotiable.

Availability

OPA348AIDRG4 is available at Aetrix Electronics and suitable for smoke detection systems, CO monitoring equipment, and portable medical instrumentation requiring stable component supply across extended temperature and long product lifecycles.

Supply support for OPA348AIDRG4 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 company specializing in analog and embedded processing technologies, with leadership in precision amplifiers, data converters, and power management ICs.

The OPAx348 product line was designed specifically for ultra-low-power, single-supply sensor signal conditioning in safety-critical portable and industrial applications - prioritizing rail-to-rail operation, sub-picoamp bias, and extended temperature reliability.

FAQ

What is the maximum capacitive load the OPA348AIDRG4 can drive in unity-gain configuration?

The OPA348AIDRG4 can directly drive up to 250 pF of pure capacitive load while maintaining stability in unity-gain configuration. For larger loads, a small series resistor (10–20 Ω) between the output and load improves phase margin without degrading DC accuracy - a technique validated in TI's SBOS213H datasheet Figure 22. This capability makes OPA348AIDRG4 well-suited for driving ADC input capacitance such as that of the ADS7822.

Does the OPA348AIDRG4 support true rail-to-rail input operation below ground or above V+?

Yes - the OPA348AIDRG4 input common-mode range extends from (V–) – 0.2 V to (V+) + 0.2 V, enabling valid operation 200 mV beyond both supply rails. This is achieved via parallel N- and P-channel input stages. Inputs beyond this range (but within absolute max ±0.5 V) won't damage the device, though parameters like PSRR and offset may degrade. The OPA348AIDRG4 thus supports direct interfacing with sensors whose outputs swing slightly below GND or above V+.

What is the typical input offset voltage drift of the OPA348AIDRG4 over temperature?

The OPA348AIDRG4 exhibits a typical input offset voltage drift of 4 µV/°C across the full operating temperature range of –40°C to +125°C. This value is specified in the Electrical Characteristics table (Section 6.7) of the SBOS213H datasheet. Such low drift ensures minimal calibration drift in long-duration measurements - critical in applications like CO detectors and industrial transmitters where baseline stability directly impacts safety compliance.

Can the OPA348AIDRG4 operate from a 2.1 V supply, and what performance trade-offs occur?

Yes - the OPA348AIDRG4 is fully specified and tested down to 2.1 V supply voltage. At 2.1 V, key parameters remain functional: rail-to-rail input/output swing is preserved, GBW remains ~1 MHz, and quiescent current stays near 45 µA. However, output drive strength decreases slightly, and large-signal settling time increases marginally. These characteristics are confirmed in Section 7.3.1 and Typical Characteristics plots (Figures 5–9) of the SBOS213H datasheet, validating OPA348AIDRG4 for coin-cell–powered designs.

Which package variant does OPA348AIDRG4 correspond to, and what are its thermal characteristics?

OPA348AIDRG4 uses the 8-pin SOIC (D package) with 4.90 mm × 3.91 mm body size. Its thermal metrics include R_θJA = 142°C/W (junction-to-ambient), R_θJB = 83°C/W (junction-to-board), and ψ_JT = 40°C/W (junction-to-top). These values - documented in Section 6.4 of SBOS213H - confirm suitability for moderate-power-density PCB layouts without forced airflow, supporting reliable operation in sealed enclosures typical of smoke and gas detection hardware.