Texas Instruments INA117SM

Overview

INA117SM from Texas Instruments is a precision unity-gain high common-mode voltage difference amplifier designed for accurate differential measurement in harsh industrial and test environments. It supports ±200V common-mode input range (VS = ±15V), delivers 0.05% max gain error, 0.001% max nonlinearity, 70dB min CMRR, and operates across –40°C to +85°C - enabling direct replacement of isolation amplifiers in servo drive current sensing and ATE applications.

For engineers reviewing the INA117SM datasheet, INA117SM pinout, INA117SM application, or INA117SM equivalent, key selection criteria include verified ±500V input protection, CSO: SHE fabrication flow performance (200kHz BW, 1.7–2.6 V/µs slew rate), SO-8 package compatibility, and reference pin flexibility for offset/CMR trimming in high-voltage monitoring circuits.

Technical Context

The INA117SM implements a monolithic precision op amp with laser-trimmed thin-film resistor network (380kΩ × 3, 19kΩ, 20kΩ) to achieve high-ratio matching critical for CMRR. Its transfer function is V_OUT = V_+IN – V_–IN + 20×V_REFA – 19×V_REFB, enabling programmable output offset and common-mode range shifting without external components.

Input protection circuitry clamps transient overloads up to ±500V on both common-mode and differential paths, while internal ESD structures meet ±1500V HBM and ±1000V CDM standards. Thermal design leverages SO-8 package θ_JA = 150°C/W, supporting operation at full specification under continuous load within ambient limits.

Key Specifications

Pinout & Package

INA117SM is housed in an SO-8 surface-mount package (3.91mm × 4.9mm), RoHS-compliant, with moisture sensitivity level (MSL) 3 and peak reflow temperature of 260°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high common-mode voltage difference amplifier applications.

Compared with INA149IP and AMC1301DWVR, the INA117SM offers optimal balance of SO-8 footprint, reference-pin programmability, and ±500V transient robustness - making it the preferred choice for cost-sensitive, space-constrained industrial monitoring where galvanic isolation is not mandated by safety standards.

Availability

INA117SM is available at Aetrix Electronics and suitable for motor control systems, automated test equipment, ultrasound imaging subsystems, and industrial machine tool voltage monitoring requiring stable component supply and long-term production continuity.

Supply support for INA117SM 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 amplifiers and high-reliability industrial ICs.

The INA117 product line was engineered specifically for high-voltage differential measurement in non-isolated industrial instrumentation - targeting applications where cost, size, and power efficiency outweigh mandatory safety isolation requirements.

FAQ

What is the maximum common-mode voltage the INA117SM can handle continuously?

The INA117SM supports a continuous common-mode input voltage range of ±200V when operated with ±15V supplies. This rating is specified under Recommended Operating Conditions and verified across the full –40°C to +85°C temperature range. Transient overloads up to ±500V are tolerated on both common-mode and differential inputs without damage, per Absolute Maximum Ratings. The INA117SM maintains specified performance within the ±200V continuous window.

Does the INA117SM require external trimming for precision applications?

The INA117SM does not require external trimming for standard operation due to its laser-trimmed internal resistor network, which guarantees ≤0.05% gain error and ≥70dB CMRR. However, optional offset voltage or CMR trim circuits (using pins 1 and 5) are documented in the datasheet for applications demanding <10µV offset or >86dB CMRR. These trims are only needed when source impedances exceed 75Ω on input pins or 4Ω on reference pins - conditions uncommon in well-designed PCB layouts.

How does the INA117SM's REFA and REFB pins affect its transfer function?

The INA117SM's transfer function is V_OUT = V_+IN – V_–IN + 20×V_REFA – 19×V_REFB. This architecture allows precise output offset control and common-mode range translation without external components. For example, grounding REFB and applying +2.5V to REFA shifts the output by +50V - enabling measurement of high-side signals with single-supply operation. This capability is intrinsic to the INA117SM's monolithic design and fully supported in all CSO: SHE devices.

Can the INA117SM operate from a single supply?

Yes, the INA117SM supports single-supply operation from 10V to 36V, as confirmed in Section 5.3 Recommended Operating Conditions. When using single supply, the common-mode input range becomes asymmetric (e.g., 0V to V_S–2V), and reference pins (REFB/REFA) must be biased appropriately to center the output swing. The device maintains full specification for gain error, nonlinearity, and CMRR under single-supply conditions - verified for CSO: SHE flow in the INA117SM variant.

What is the bandwidth and slew rate of the INA117SM, and how do they vary by fabrication flow?

The INA117SM is manufactured exclusively in the CSO: SHE fabrication flow, delivering a guaranteed –3dB bandwidth of 200kHz and slew rate of 1.7–2.6 V/µs. These values are distinct from the TID flow (500kHz, 1.7–5 V/µs) and are explicitly assigned to INA117SM in Table 8-1 Device Nomenclature. The 200kHz bandwidth supports accurate measurement of 50kHz sinusoidal currents with <0.1% amplitude error, while the 2.6 V/µs max slew rate ensures <6.5µs settling to 0.1% for 10V output steps.