Texas Instruments PGA204AU/1K

Overview

PGA204AU/1K from Texas Instruments (formerly Burr-Brown) is a digitally programmable gain instrumentation amplifier with four precision gain settings (1, 10, 100, 1000 V/V), ±40V input over-voltage protection, and laser-trimmed 50µV max input offset voltage. It operates from ±4.5V to ±18V supplies and is used in high-accuracy sensor signal conditioning for data acquisition systems.

For engineers reviewing the PGA204AU/1K datasheet, PGA204AU/1K pinout, PGA204AU/1K application, or PGA204AU/1K equivalent, key selection criteria include gain-switching settling time (≤1000 µs at G=1000), CMRR up to 115 dB at G=1000, input bias current ≤2 nA, and SOIC-16 surface-mount packaging for automated assembly.

Technical Context

The PGA204AU/1K implements a three-op-amp instrumentation architecture with digitally selected thin-film resistor feedback networks. Gain is set via TTL/CMOS-compatible A0 and A1 address inputs, enabling immediate gain change without latching. Internal over-voltage protection on both inputs withstands ±40V independent of power supply presence.

It features dual-stage laser trimming for offset (50 µV max) and drift (0.25 µV/°C), and its output stage (A3) references the Ref pin-requiring low-impedance grounding to maintain >110 dB CMRR. The Feedback pin (12) must be connected directly to VO (11) for standard operation.

Key Specifications

Pinout & Package

SOL-16 (SOIC-16, package code DW) surface-mount package, 10.3 mm × 7.5 mm body, 1.27 mm pitch, RoHS-compliant NiPdAu lead finish, MSL Level-3 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable-gain instrumentation amplifier applications.

Compared with INA128UA and AD8253ARMZ, PGA204AU/1K uniquely combines TTL/CMOS-compatible parallel gain control, integrated ±40V input protection, and laser-trimmed DC precision in a cost-optimized SOIC-16 package - making it optimal for industrial DAQ where robustness and simplicity outweigh SPI complexity or ultra-low power needs.

Availability

PGA204AU/1K is available at Aetrix Electronics and suitable for data acquisition systems, medical instrumentation, general-purpose analog boards, and industrial sensor interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for PGA204AU/1K 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 acquired Burr-Brown in 2000 and maintains full product support, manufacturing, and qualification for legacy precision analog ICs including the PGA204 series.

The PGA204 product line was designed specifically for high-accuracy, digitally configurable sensor signal conditioning in industrial and medical instrumentation - emphasizing DC precision, input ruggedness, and ease of integration over high-speed performance.

FAQ

What gain settings does the PGA204AU/1K support, and how are they selected?

The PGA204AU/1K supports four discrete gain settings: 1, 10, 100, and 1000 V/V. These are selected using two TTL/CMOS-compatible digital inputs - A0 (pin 15) and A1 (pin 16) - with logic states decoded per the datasheet table (e.g., A1A0 = 11 selects G=1000). PGA204AU/1K has no internal latch; gain changes occur immediately upon input transition, with settling time dependent on selected gain (e.g., 1000 µs for 0.1% at G=1000).

Does the PGA204AU/1K require an external logic supply voltage for its digital inputs?

No, the PGA204AU/1K does not require a separate logic supply. Its digital inputs (A0, A1, and Digital Ground) operate from the same ±4.5V to ±18V analog supplies. Digital Ground (pin 14) may be connected to V– or system ground, and logic "1" is defined as ≥2V above Digital Ground potential. PGA204AU/1K draws ~1.3 mA through Digital Ground, so a dedicated low-impedance return path is recommended.

How is the output of the PGA204AU/1K referenced, and why is the Ref pin critical?

The output voltage of the PGA204AU/1K is referenced to the Ref pin (pin 10), not to ground or V–. This allows level-shifting and isolated referencing in multi-channel or floating systems. PGA204AU/1K requires a low-impedance connection (<5 Ω) to Ref - otherwise, CMRR degrades significantly (e.g., to ~80 dB at G=1). A buffered voltage or clean ground should drive Ref; direct connection to noisy digital ground compromises performance.

Can the PGA204AU/1K be used with single-supply operation?

The PGA204AU/1K is specified for dual-supply operation (±4.5V to ±18V) and is not characterized for true single-supply use. While it may function with asymmetric rails (e.g., +15V/0V), the input common-mode range and output swing become severely limited - especially at high gains. For single-supply applications, TI recommends alternatives like the INA333 or AD8237. PGA204AU/1K's design assumes symmetrical rails to achieve its full ±12.7V input range and ±10V output swing.

What is the purpose of the Feedback pin (pin 12) on the PGA204AU/1K?

The Feedback pin (pin 12) on the PGA204AU/1K must be connected directly to the main output (VO, pin 11) for standard operation. This connection closes the internal feedback loop of the output difference amplifier (A3). It also enables remote sensing: routing the Feedback trace to the load instead of VO improves accuracy by compensating for IR drops in output traces - a capability unique to the PGA204AU/1K's three-op-amp topology.