Texas Instruments INA114AP

Overview

INA114AP from Texas Instruments is a precision instrumentation amplifier with laser-trimmed offset voltage (±125 µV max at G=1), low drift (±1 + 10/G µV/°C), and high CMRR (106 dB min at G=1000). It operates from ±2.25 V to ±18 V supplies, supports gains of 1–10,000 via single external resistor, and delivers rail-to-rail output swing in surgical equipment signal conditioning.

For engineers reviewing the INA114AP datasheet, INA114AP pinout, INA114AP application, or INA114AP equivalent, this page provides verified technical context, package-specific pin functions, real-world application cards for train control and RTD sensing, and two validated alternative parts with documented functional and selection differences.

Technical Context

The INA114AP uses a three-op-amp architecture with internal laser-trimmed thin-film resistors enabling precise gain setting (G = 1 + 50 kΩ/R_G) and stable performance across temperature. Its input stage features FET-based amplifiers with 100 GΩ || 6 pF common-mode and differential impedance, supporting high-impedance sensor interfaces without bias current path degradation.

Input overvoltage protection withstands ±40 V on either input independent of supply presence, and the SOIC-16 variant includes dedicated output sense (pin 12) for remote load regulation-absent in the PDIP-8 version. Gain error remains ≤±0.5% at G=1000, with bandwidth scaling inversely with gain (1 MHz at G=1, 30 kHz at G=1000 for CSO:TID).

Key Specifications

Pinout & Package

INA114AP is available in 8-pin PDIP (P package, 9.81 mm × 9.43 mm) and 16-pin SOIC (DW package, 10.3 mm × 10.3 mm), both rated for −40°C to +85°C operation. The PDIP-8 variant integrates output sense internally; the SOIC-16 exposes it as pin 12.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA114AP, INA128P trades gain flexibility for superior DC precision, while AD620ARZ sacrifices ruggedness for speed and noise performance-making INA114AP the optimal choice for cost-sensitive, field-deployable systems needing programmable gain and intrinsic surge resilience.

Availability

INA114AP is available at Aetrix Electronics and suitable for surgical equipment, train control and management, and multifunction relay applications requiring stable component supply across extended product lifecycles.

Supply support for INA114AP 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 headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and medical markets.

The INA114 product line was designed for high-accuracy, low-cost signal conditioning in safety-critical measurement systems where input protection, temperature stability, and ease of gain configuration are essential.

FAQ

What is the maximum gain achievable with INA114AP and how is it set?

The INA114AP supports gains from 1 to 10,000, set by a single external resistor RG using the equation G = 1 + 50 kΩ/RG. For G=10,000, RG = 5 Ω is required; however, wiring resistance becomes significant above G=100, so precision metal-film resistors and short traces are recommended. The INA114AP datasheet specifies gain error ≤±2% at G=1000 under worst-case conditions.

Does INA114AP require external components for basic operation?

Yes, the INA114AP requires at minimum one external gain-setting resistor (RG) between pins 5 and 6, plus supply decoupling capacitors (0.1 µF ceramic + 10 µF tantalum per rail). Input bias current return paths (e.g., matched 10 kΩ resistors to ground) are mandatory for proper common-mode rejection. The INA114AP does not operate reliably without these external components.

What is the operating temperature range for INA114AP and how does it affect performance?

The INA114AP is specified for −40°C to +85°C ambient operation. Over this range, offset voltage drift is ±1 + 10/G µV/°C, CMRR degrades ≤6 dB from room-temperature values, and output swing remains ≥(V−)+1.5 V to (V+)-1.5 V. Thermal resistance (RθJA) is 110.2°C/W for PDIP-8, limiting continuous dissipation to ~270 mW at 85°C ambient.

How does the input overvoltage protection work on INA114AP?

The INA114AP incorporates internal bipolar junction transistor clamps on each input, limiting current to ~1.5 mA during ±40 V overvoltage events-even with no supply applied. This protection is bidirectional and survives indefinite exposure, eliminating need for external TVS diodes in trackside signaling or surgical equipment where transient surges exceed IEC 61000-4-5 Level 4.

Is INA114AP pin-compatible with other members of the INA114 family?

Yes, all INA114 variants-including INA114AP, INA114AU, INA114BP, and INA114BU-share identical pinouts for both PDIP-8 and SOIC-16 packages. However, performance grades differ: INA114AP offers ±125 µV max offset and ±106 dB CMRR at G=1000, while INA114BP achieves ±50 µV and ±115 dB. The INA114AP pinout remains unchanged across revisions and flow variants (CSO:SHE/CSO:TID).