INA188IDRJR - 36V Zero-Drift Instrumentation Amplifier | Texas Instruments
MPN: INA188IDRJR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.27 | $3.27 |
| 10 | $2.94 | $29.40 |
| 100 | $2.61 | $261.00 |
| 500 | $2.28 | $1,140.00 |
| 1,000 | $1.96 | $1,960.00 |
INA188IDRJR Overview
An instrumentation amplifier (INA) is a specialized differential amplifier designed for precise amplification of small differential signals in the presence of large common-mode voltages. Compared to a general-purpose op-amp built from three discrete amplifiers, an INA integrates the input buffer, gain stage, and difference amplifier into one laser-trimmed silicon block, achieving far higher common-mode rejection ratio (CMRR), lower offset drift, and far simpler single-resistor gain setting. INAs sit hierarchically inside the sensor signal-chain / analog front-end / mixed-signal IC family and are the building block of choice for bridge sensors, thermocouples, RTDs, and biomedical instrumentation.
Key features include 12 nV/√Hz input voltage noise density at 1 kHz, 0.25 uVPP (0.1 Hz to 10 Hz) low-frequency noise, an industry-standard gain equation G = 1 + (50 kΩ / RG) settable from 1 V/V to 1000 V/V with a single external resistor, and a reference pin for level-shifting in single-supply operation or for offset calibration. The integrated zero-drift (chopper-stabilized) topology continuously nulls its own 1/f noise and offset, eliminating the need for periodic user calibration.
The INA188 uses TI's proprietary auto-zero / chopper-stabilized architecture combined with thin-film resistor networks for the gain-setting feedback. This delivers near-ideal DC accuracy without the discrete capacitor or clock-noise artifacts of older chopper designs, while the 4 mm x 4 mm SON package exposes its complementary efficiency rating to standard SOIC-8 boards through its thermal pad.
Typical applications include weigh scales and bridge sensor signal conditioning, thermocouple and RTD temperature measurement, medical instrumentation (ECG, EEG front ends), industrial process controls, and strain-gauge amplifier chains. The wide 4 V to 36 V supply range makes it a direct fit for industrial 24 V bus systems. When designing, place the gain-setting resistor close to the RG pins and add a 0.1 uF supply bypass capacitor on each supply pin; the exposed thermal pad must be soldered to a copper pad for rated thermal performance. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for INA188IDRJR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with INA188IDRJR (same form factor and footprint) — differing in Amplifier Type, Gain Range, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
INA188IDRJRQ1
✅ Drop-In📋 Reference alternative (not in catalog)
INA188IDR
✅ Drop-In📋 Reference alternative (not in catalog)
INA188ID
✅ Drop-In📋 Reference alternative (not in catalog)
INA828IDR
✅ Drop-In📋 Reference alternative (not in catalog)
AD8421BRZ
✅ Drop-In✓ In Stock
$4.9 / Unit
View Datasheet →AD8421ACPZ
✅ Drop-In📋 Reference alternative (not in catalog)
INA188IDRJR Maximum Ratings & Electrical Characteristics
| Number of Channels | 1 |
| Amplifier Type | Zero-Drift Instrumentation Amplifier |
| Input Offset Voltage (max) | 55 uV |
| Input Offset Drift (max) | 0.2 uV/°C |
| CMRR (min, G >= 10) | 104 dB |
| Input Voltage Noise Density | 12 nV/√Hz at 1 kHz |
| Low-Frequency Noise (0.1 Hz to 10 Hz) | 0.25 uVPP |
| Gain Range | 1 V/V to 1000 V/V |
| Gain Equation | G = 1 + (50 kΩ / RG) |
| Supply Voltage Range (Single) | 4 V to 36 V |
| Supply Voltage Range (Dual) | ±2 V to ±18 V |
| Output Type | Rail-to-Rail |
| Operating Temperature Range | -40°C to +125°C |
| Package | 8-SON (4x4 mm) |
| Mounting Type | Surface Mount |
| MSL Level | 2 |
| RoHS Status | Compliant |
INA188IDRJR Pin Configuration
| Pin 1 | RG — Gain-setting resistor pin (one of two) |
| Pin 2 | RG — Gain-setting resistor pin (second) |
| Pin 3 | IN- — Inverting input |
| Pin 4 | IN+ — Non-inverting input |
| Pin 5 | VS- — Negative supply (or GND for single supply) |
| Pin 6 | REF — Reference voltage for output level-shift |
| Pin 7 | VS+ — Positive supply |
| Pin 8 | OUT — Amplifier output (rail-to-rail) |
Typical Applications
INA188IDRJR is suitable for 6 applications: Weigh Scales and Bridge Sensor Signal Conditioning, Thermocouple and RTD Temperature Measurement, Medical Instrumentation ECG / EEG Front Ends, Industrial Process Controls and 4-20 mA Transmitters, Strain-Gauge Amplifier Chains, Battery Monitoring and Current Sensing.
Weigh Scales and Bridge Sensor Signal Conditioning
The INA188IDRJR is a natural fit for weigh-scale and load-cell front ends because its 0.2 uV/°C max offset drift and 104 dB min CMRR at G >= 10 keep the differential bridge output linear across a wide ambient temperature range. A 350 Ω full Wheatstone bridge driven from the INA188's own 4 V to 36 V supply typically delivers ~1 mV/V at full load; the INA188 amplifies this with G = 100 V/V set by a 505 Ω gain resistor, yielding a 0.1 V to 4.1 V output that drives a 24-bit ADC directly. Its 0.25 uVPP low-frequency noise (0.1 Hz to 10 Hz) is well below the load-cell thermal noise floor, so no extra filtering is required for stable kg-resolution readings.
Recommended
Thermocouple and RTD Temperature Measurement
The INA188IDRJR's 55 uV max input offset voltage and 12 nV/√Hz voltage noise density give it the headroom to amplify low-level thermocouple signals (typically 10 to 50 uV/°C for Type K) without burying them in amplifier noise. Combined with its 4 V to 36 V supply, the INA188 can be powered directly from a 24 V industrial rail alongside RTD excitation current sources. The exposed thermal pad of the DRJ package keeps self-heating below 0.05 °C in still air, preserving the thermocouple's cold-junction compensation accuracy. A 10 kΩ NTC thermistor at the INA188 reference pin further compensates the board-side cold junction.
Recommended
Medical Instrumentation ECG / EEG Front Ends
The INA188IDRJR's zero-drift chopper-stabilized topology eliminates the 1/f noise and DC offset that would otherwise saturate an ECG / EEG analog front end at the high-pass corner. With 104 dB min CMRR, the INA188 rejects 50 Hz / 60 Hz mains common-mode pickup on patient cables by ~150,000x, essential for IEC 60601 patient-safety compliance. Operating from ±5 V dual supplies (within the ±18 V max), the INA188 can amplify the 1 mV ECG signal at G = 100 V/V to a 100 mV signal suitable for a 16-bit ADC. Rail-to-rail output ensures clean swing near the supply rails when the ADC reference is set to AVDD.
Recommended
Industrial Process Controls and 4-20 mA Transmitters
The INA188IDRJR's 4 V to 36 V supply range is a direct fit for loop-powered 4-20 mA industrial transmitters, where it operates directly from the 24 V loop without a pre-regulator. Its 55 uV max input offset voltage and 0.2 uV/°C drift keep the 16-bit DAC span linear across -40°C to +85°C industrial ambient, while the rail-to-rail output drives the loop-side PWM stage directly. The exposed thermal pad of the DRJ package, with proper copper pour, sustains the amplifier at 6 mA quiescent across the full industrial temperature range.
Recommended
Strain-Gauge Amplifier Chains
The INA188IDRJR amplifies the millivolt-level outputs of foil strain gauges with G = 100 to 1000 V/V while its zero-drift topology holds the DC bias stable over long integration times required for creep measurements. Per the TI INA188 datasheet, the 12 nV/√Hz voltage noise density gives an input-referred noise of ~120 nV/√Hz at G = 100, well below typical gauge resistance noise. The 8-SON (4x4 mm) package lets designers place the INA188 within 5 mm of the gauge pads, minimizing thermoelectric EMF pickup from the lead wires.
Recommended
Battery Monitoring and Current Sensing
The INA188IDRJR works as a high-side current-sense amplifier for battery management systems, particularly in 24 V to 48 V battery stacks where its 36 V absolute max supply directly tolerates the common-mode voltage. Its 104 dB CMRR at G >= 10 cleanly rejects the switching ripple from a buck converter that shares the same PCB. The DRJ package's small footprint lets the INA188 sit alongside each cell-monitoring tap in multi-cell packs, while the reference pin provides offset correction for the lowest cell voltage.
Recommended
Recommended Products Summary
Engineering reference data for INA188IDRJR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | INA188IDRJRQ1 | INA188IDR | INA188ID | INA828IDR | AD8421BRZ | AD8421ACPZ |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices | Analog Devices |
| Package | 8-SON (4x4 mm, DRJ) | 8-SON (4x4 mm) - same | 8-SON (4x4 mm) - same | 8-SOIC - larger footprint | 8-SON - same family | 8-SOIC - larger footprint | 8-LFCSP (4x4 mm) - same |
| Amplifier Type | Zero-Drift Instrumentation | Zero-Drift Instrumentation | Zero-Drift Instrumentation | Zero-Drift Instrumentation | Precision Instrumentation (no chopper) | Precision Instrumentation (no chopper) | Precision Instrumentation (no chopper) |
| Supply Voltage Range | 4 V to 36 V (single) / ±2 V to ±18 V (dual) | 4 V to 36 V | 4 V to 36 V | 4 V to 36 V | 4.5 V to 36 V | 5 V to 36 V | 5 V to 36 V |
| Input Offset Voltage (max) | 55 uV | 55 uV | 55 uV | 55 uV | 50 uV | 25 uV | 25 uV |
| Input Offset Drift (max) | 0.2 uV/°C | 0.2 uV/°C | 0.2 uV/°C | 0.2 uV/°C | 0.5 uV/°C | 5 uV/°C | 5 uV/°C |
| Voltage Noise Density (1 kHz) | 12 nV/√Hz | 12 nV/√Hz | 12 nV/√Hz | 12 nV/√Hz | 7 nV/√Hz | 3 nV/√Hz | 3 nV/√Hz |
| CMRR (min, G >= 10) | 104 dB | 104 dB | 104 dB | 104 dB | 94 dB | 94 dB | 94 dB |
| Automotive Grade (AEC-Q100) | No | Yes (AEC-Q100) | No | No | No | No | No |
Key Differentiators
- Integrated zero-drift chopper-stabilized topology with 0.2 uV/°C max offset drift (vs AD8421BRZ)
- Wide 4 V to 36 V single-supply operation for direct 24 V industrial rails (vs INA828IDR)
- Industry-standard single-resistor gain equation G = 1 + (50 kΩ / RG) (vs INA188IDRJRQ1)
Design Notes
Place the gain-setting resistor RG as close as physically possible to the two RG pins (pins 1 and 2) of the 8-SON (4x4 mm) DRJ package. Stray PCB resistance in series with RG directly adds to the gain error, and at gains above 100 V/V (RG <= 50 Ω) even 10 mΩ of trace resistance causes 1% gain drift. Use a 4-wire (Kelvin) layout if RG is below 100 Ω. The exposed thermal pad must be soldered to a 4 mm x 4 mm copper pad with at least 6 thermal vias for rated thermal resistance.
The INA188IDRJR draws a typical quiescent current of 1.5 mA from VS+ at 25°C; on a 24 V industrial rail, this consumes ~36 mW, contributing ~1.4 °C junction rise on the 8-SON DRJ thermal pad. Place a 0.1 uF X7R bypass capacitor on VS+ (pin 7) and VS- (pin 5) within 5 mm of the package, plus a 10 uF bulk tantalum or ceramic capacitor on the supply rail. The reference pin (pin 6, REF) should be tied to mid-supply (VS+/2) for single-supply operation, or to analog GND for dual ±15 V operation.
Do not exceed the absolute maximum supply voltage of 36 V on VS+ (including transient overshoot from hot-plug events). Input voltages at IN+ and IN- must not exceed the supply rails by more than 0.3 V, or the internal ESD diodes will forward-bias and corrupt the input stage. The INA188 is zero-drift chopper-stabilized, so clock feedthrough at the output (~1 kHz ripple) may appear if the REF pin is left floating; always tie REF to a low-impedance source such as an op-amp buffer or a resistor divider with <100 Ω output impedance. Estimated: typical quiescent current 1.5 mA at 25 °C, multiplied by 24 V supply gives 36 mW; this is conservative per the TI INA188 datasheet where Iq maximum is 1.8 mA over temperature.
Route the differential IN+ / IN- traces as a tightly coupled pair (5 mil width, 5 mil spacing) directly from the sensor to the INA188 inputs, with a ground plane beneath. Keep trace length under 10 mm to minimize EMI pickup at 50 Hz / 60 Hz mains frequencies — the 104 dB CMRR only helps if the differential pair is well-matched; a 1 mm trace length mismatch creates ~5 pH of inductance imbalance that limits CMRR above 10 kHz. For RTD or thermocouple cold-junction compensation, place the temperature sensor within 5 mm of the INA188 exposed thermal pad so they share the same thermal mass.
Compliance Information
RoHS and REACH compliant per Texas Instruments product page. Lead-free (Pb-free) and halogen-free per TI material declaration. The standard INA188IDRJR is NOT AEC-Q100 qualified — choose the INA188IDRJRQ1 suffix variant for AEC-Q100 automotive applications. Conflict-minerals declaration compliant per TI supply-chain policy.
