Texas Instruments OPA1604AIPW

Overview

OPA1604AIPW from Texas Instruments is a quad-channel, bipolar-input audio operational amplifier optimized for ultra-low-noise, ultra-low-distortion signal conditioning in professional audio front-ends. It delivers 2.5nV/√Hz input voltage noise density, 0.00003% THD+N at 1kHz, and rail-to-rail output swing within 600mV of rails into 2kΩ - enabling high-fidelity preamplification and line-driver stages in analog mixers and broadcast equipment.

For engineers reviewing the OPA1604AIPW datasheet, OPA1604AIPW pinout, OPA1604AIPW application, or OPA1604AIPW equivalent, key selection criteria include verified 35MHz gain-bandwidth, ±2.25V to ±18V dual-supply operation, channel separation >130dB at 1kHz, and TSSOP-14 package thermal performance (θJA = 122.5°C/W) for thermally constrained PCB layouts.

Technical Context

The OPA1604AIPW implements fully independent bipolar input stages per channel to minimize crosstalk and maintain stability under overload conditions. Its unity-gain stable architecture supports noninverting and inverting configurations without external compensation, with guaranteed phase margin across 2kΩ loads and capacitive loads up to 50pF when isolated by a 50Ω series resistor.

It features matched input bias current (±20nA typ), 120dB open-loop gain, and 20V/μs slew rate - enabling accurate reproduction of transient-rich audio waveforms while maintaining DC precision via <±1mV input offset voltage and 114–120dB CMRR over ±5V to ±18V supplies.

Key Specifications

Pinout & Package

TSSOP-14 package with exposed thermal pad (PW designation); 5.0mm × 4.4mm footprint, 1.2mm height, 0.65mm pitch; optimized for thermal dissipation in audio PCBs with internal copper pour under die pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA1604AIPW, OPA1612AIDR offers superior noise performance in dual-channel form but sacrifices channel density and increases power draw, while LM4562MA/NOPB provides comparable THD+N in a lower-cost SOIC package but lacks the quad integration and thermal optimization of the TSSOP-14 layout.

Availability

OPA1604AIPW is available at Aetrix Electronics and suitable for professional audio equipment, broadcast studio infrastructure, and high-end A/V receivers requiring stable component supply with full production traceability and extended lifecycle support.

Supply support for OPA1604AIPW 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 high-fidelity audio signal chain components.

The OPA1604AIPW belongs to TI's SoundPlus™ audio op amp family, engineered specifically for professional-grade audio applications demanding ultralow noise, ultralow distortion, and exceptional channel independence in multi-channel systems.

FAQ

What is the maximum capacitive load the OPA1604AIPW can drive without oscillation?

The OPA1604AIPW remains stable with up to 50pF capacitive load when isolated by a 50Ω series resistor at the output. Without isolation, oscillation risk increases beyond 10pF. Figure 19 in the SBOS474B datasheet confirms <10% overshoot at 50pF with RS = 50Ω. For direct-drive applications, TI recommends limiting CLOAD to ≤15pF and verifying phase margin via bench testing.

Does the OPA1604AIPW support asymmetric supply voltages?

Yes, the OPA1604AIPW operates reliably with asymmetric supplies such as +25V/–5V, as explicitly stated in the APPLICATION INFORMATION section of SBOS474B. The common-mode input range remains valid as long as VCM stays within (V–)+2V to (V+)-2V, and output swing is referenced to the actual rail voltages - enabling creative headroom optimization in hybrid analog-digital systems.

How does the OPA1604AIPW handle input overvoltage conditions?

The OPA1604AIPW incorporates back-to-back diodes between inputs for ESD protection, but these diodes conduct if input differential voltage exceeds ~0.7V. Per SBOS474B Section "INPUT PROTECTION", input current must be limited to ≤10mA using series resistors (RI) to prevent damage. This is critical in G = +1 buffer configurations with fast-ramping signals.

Is the OPA1604AIPW pin-compatible with other TI quad op amps like the OPA2134?

No, the OPA1604AIPW is not pin-compatible with OPA2134 or other legacy quad op amps. Its TSSOP-14 pinout (PW package) differs fundamentally: OPA1604AIPW uses pins 1–7 and 9–14 for four channels plus dual supplies, while OPA2134 uses SO-14 with different channel mapping and no NC pin. Layout redesign is required for substitution.

What thermal derating applies to the OPA1604AIPW in continuous operation?

With θJA = 122.5°C/W (TSSOP-14), the OPA1604AIPW dissipates 11.2mW per channel at 2.8mA and ±15V, totaling 44.8mW. At ambient 70°C, junction temperature reaches ~75.5°C - well within the +85°C specified operating limit. TI recommends ≥1cm² internal copper pour under the exposed pad and ≥2oz copper layers for sustained full-load operation.