Texas Instruments OPA2325IDGKR

Overview

OPA2325IDGKR from Texas Instruments is a dual-channel, precision rail-to-rail input/output CMOS operational amplifier optimized for low-noise (9 nV/√Hz at 10 kHz), wide bandwidth (10 MHz), and low quiescent current (650 µA per channel), serving as an ADC input driver in battery-powered data acquisition systems.

For engineers reviewing the OPA2325IDGKR datasheet, OPA2325IDGKR pinout, OPA2325IDGKR application, or OPA2325IDGKR equivalent, key selection criteria include zero-crossover distortion performance, ±150 µV max offset voltage, 114 dB CMRR, 5 V/µs slew rate, and compatibility with unregulated 2.2–5.5 V single-supply operation.

Technical Context

The OPA2325IDGKR implements a zero-crossover input stage using an internal charge pump to bias a single differential pair across the full common-mode range - eliminating transition-induced CMRR degradation seen in conventional complementary-input CMOS op amps. This architecture enables stable 114 dB CMRR over ±2.85 V input common-mode swing.

It delivers rail-to-rail output swing within 10 mV of both rails under 10 kΩ load, supports unity-gain stability with up to 15 pF capacitive load, and maintains 10 MHz gain bandwidth with 5 V/µs slew rate - making it suitable for driving SAR ADCs requiring fast settling (<1 µs to 0.01%) and low THD+N (0.0005% at 10 kHz).

Key Specifications

Pinout & Package

OPA2325IDGKR is packaged in an 8-pin VSSOP (DGK) with 3.00 mm × 3.00 mm body size and 0.65 mm pitch - optimized for space-constrained PCB layouts while maintaining thermal resistance of 143 °C/W (junction-to-ambient).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision op amp applications.

Compared with OPA2325IDGKR, OPA2182IDR offers tighter DC specs at reduced bandwidth and higher power, while ADA4522-2ARMZ provides zero-drift stability at the cost of speed - making OPA2325IDGKR optimal for balanced precision, noise, and 10-MHz signal fidelity in battery-operated systems.

Availability

OPA2325IDGKR is available at Aetrix Electronics and suitable for high-precision sensor interfaces, portable test equipment, and industrial analog input modules requiring stable component supply and guaranteed long-term manufacturability.

Supply support for OPA2325IDGKR 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 op amp design and manufacturing.

The OPAx325 family was engineered specifically for high-resolution data acquisition systems where zero-crossover distortion, low noise, and rail-to-rail operation are essential - targeting battery-powered instrumentation and industrial sensing.

FAQ

What is the maximum capacitive load the OPA2325IDGKR can drive while remaining stable?

The OPA2325IDGKR is unity-gain stable with capacitive loads up to 15 pF, as verified in the datasheet's Typical Characteristics (Figure 27). Driving larger loads (e.g., ADC input capacitance >15 pF) requires an isolation resistor (typically 10–50 Ω) between the amplifier output and the load to maintain phase margin above 67°.

Does the OPA2325IDGKR support dual-supply operation, and what are the limits?

Yes, the OPA2325IDGKR supports dual-supply operation from ±1.1 V to ±2.75 V (total supply ≤5.5 V), as specified in the Recommended Operating Conditions table. It maintains full rail-to-rail input common-mode range and output swing across this range, enabling bipolar signal conditioning in legacy industrial systems.

How does the zero-crossover architecture of the OPA2325IDGKR improve performance versus standard rail-to-rail op amps?

The OPA2325IDGKR uses an internal charge pump to power a single linear input stage across the entire common-mode range - eliminating the offset voltage discontinuity and CMRR collapse that occur at rail transitions in conventional complementary-input CMOS op amps. This yields consistent 114 dB CMRR from (V–) – 0.1 V to (V+) + 0.1 V.

Can the OPA2325IDGKR be used to drive a 600 Ω load, and what is the expected THD+N?

Yes, the OPA2325IDGKR can drive a 600 Ω load with THD+N of 0.005% at 10 kHz and 2 VPP output (per Electrical Characteristics Table). Output swing is reduced to ~3.5 VPP under this load, and thermal considerations require derating above 85°C ambient due to increased power dissipation.

What is the temperature range over which the OPA2325IDGKR guarantees its 150 µV max offset voltage specification?

The OPA2325IDGKR guarantees ≤150 µV maximum input offset voltage over the full operating temperature range of –40°C to +125°C, as stated in the Electrical Characteristics table under "OFFSET VOLTAGE" with test condition "TA = –40°C to +125°C". The typical drift is 2–7.5 µV/°C.