Texas Instruments OPA4345UAG4

Overview

OPA4345UAG4 from Texas Instruments is a quad, rail-to-rail input/output CMOS operational amplifier optimized for gains ≥5, featuring 3MHz gain-bandwidth product, 2V/µs slew rate, and 150µA typical quiescent current per amplifier. It operates from a single 2.7V–5.5V supply and delivers 1mV output swing from rail into high-impedance loads - ideal for driving sampling ADCs in low-power data acquisition systems.

For engineers reviewing the OPA4345UAG4 datasheet, OPA4345UAG4 pinout, OPA4345UAG4 application, or OPA4345UAG4 equivalent, key selection criteria include its gain-stability requirement (G ≥ 5), TSSOP-14/SO-14 package compatibility, –40°C to +85°C industrial temperature range, and verified performance in active filters and audio signal conditioning circuits.

Technical Context

The OPA4345UAG4 employs a complementary CMOS input stage enabling rail-to-rail input common-mode range extending 300mV beyond both supply rails, with a defined transition region where both N- and P-channel pairs operate. Its class AB output stage achieves 1mV rail-to-rail swing at light loads while maintaining >96dB open-loop gain.

This device is internally compensated for stable operation at closed-loop gains of 5 or greater, distinguishing it from the unity-gain-stable OPA4344 family. Its 3MHz GBW and 2V/µs slew rate support medium-speed signal conditioning without phase margin degradation in G ≥ 5 configurations.

Key Specifications

Pinout & Package

OPA4345UAG4 is packaged in a 14-pin SOIC (SO-14) surface-mount package with standard JEDEC MS-012AC footprint and 1.27mm pitch. Thermal resistance θ_JA is 100°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad rail-to-rail operational amplifier applications.

Compared with OPA4344UA and MCP6004-E/SL, the OPA4345UAG4 uniquely delivers 3MHz bandwidth and 2V/µs slew rate in a quad SO-14 package while maintaining rail-to-rail I/O and 150µA/channel quiescent current - making it optimal for medium-speed, gain ≥5 signal chains where space and power are constrained.

Availability

OPA4345UAG4 is available at Aetrix Electronics and suitable for industrial process control, portable data acquisition, and audio front-end applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for OPA4345UAG4 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 delivering analog and embedded processing solutions, with leadership in precision op amps, data converters, and power management ICs.

The OPA345/4345 family was designed specifically for low-power, rail-to-rail signal conditioning in space- and energy-constrained systems - targeting data acquisition, sensor interfaces, and portable instrumentation.

FAQ

What is the minimum recommended gain for stable operation of the OPA4345UAG4?

The OPA4345UAG4 is internally compensated for stable operation at closed-loop gains of 5 or greater. Using it at gains below 5 may cause peaking or oscillation due to reduced phase margin. For unity-gain or G = 2 applications, the pin-compatible OPA4344UA is the appropriate selection. Always verify stability with actual layout parasitics and load conditions.

Does the OPA4345UAG4 support true rail-to-rail input with signals extending beyond the supply rails?

Yes - the OPA4345UAG4 features a complementary CMOS input stage allowing common-mode voltage range from –0.3V to (V+) + 0.3V. However, inputs exceeding (V+) – 1.8V enter a transition region where PSRR, CMRR, and THD degrade. For robust performance, keep input signals within –0.3V to (V+) – 1.8V unless transient excursions are brief and infrequent.

Can the OPA4345UAG4 drive a 100pF capacitive load in a G = 5 configuration?

Yes - the OPA4345UAG4 can directly drive up to 250pF capacitive load when configured for G ≥ 5. At G = 5 and CL = 100pF, typical small-signal overshoot is <5% with 1.5µs 0.1% settling time. No series isolation resistor is needed, preserving DC accuracy and output swing integrity in filter or ADC driver applications.

What is the maximum allowable supply voltage for the OPA4345UAG4?

The absolute maximum supply voltage for the OPA4345UAG4 is 7.5V between V+ and V– pins. However, the device is fully specified and guaranteed over 2.7V to 5.5V. Operation above 5.5V voids parametric guarantees and risks reliability degradation - use only within the 2.7V–5.5V range for production designs.

How does the OPA4345UAG4's quiescent current vary with temperature and supply voltage?

Quiescent current for the OPA4345UAG4 remains tightly controlled: 150µA typical at +25°C and 5.5V, rising to ≤300µA maximum across –40°C to +85°C. It shows minimal variation with supply voltage - 145µA at 2.7V and 155µA at 5.5V - enabling predictable power budgeting in battery-operated systems.