INA121UAIn StockTexas Instruments
INA121UA is a precision FET-input instrumentation amplifier from Texas Instruments in SO-8 package, gain 1-10000 V/V, 800uV offset, priced from $2.91; in stock, 1 pc minimum, ships worldwide.
- Manufacturer
- Texas Instruments
- Package
- SO-8
- Pin Count
- 8
- Lifecycle
- ACTIVE
- Datasheet
- INA121UA Datasheet PDF
- Category
- amplifiers
- Price
- From $2.9104(MOQ 1)
- Temp Range
- -40.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- FET input: ultra-low bias current (5pA) for high-impedance sensors
- Gain 1-10000 V/V via single external resistor
- Low offset voltage 800uV max for precision measurements
- Dual supply +/-2.25V to +/-18V or single 4.5V to 36V
- SO-8 package, compact 8-pin SOIC
Applications
The INA121UA is widely used in industrial data acquisition systems, medical instrumentation, and bridge sensor amplification circuits. Its FET inputs make it ideal for interfacing with thermocouples, strain gauges, and pH electrodes. It is also commonly deployed in portable battery-powered instruments requiring low quiescent current.
Specifications
| Supply Voltage | ±2.25V to ±18V |
| Input Bias Current | ±5pA |
| Offset Voltage | 800µV max |
| Gain Range | 1 to 10000 V/V |
| Operating Temperature | -40°C to 85°C |
| Package | SO-8 |
| Input Type | FET (JFET) |
| Quiescent Current | 900µA typical |
| Package | SO-8 |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for INA121UA:
Frequently Asked Questions
What is the gain range of the INA121UA?
The INA121UA supports a gain range of 1 to 10000 V/V. Gain is set by connecting a single external resistor (RG) between pins 1 and 8. No external resistor gives unity gain (G=1); lower RG values increase gain. The formula is G = 1 + (50kΩ / RG).
What supply voltage does the INA121UA require?
The INA121UA operates from dual supplies of ±2.25V to ±18V or a single supply from 4.5V to 36V. This flexibility makes it suitable for both battery-powered portable devices and industrial systems with higher rail voltages.
What package does the INA121UA come in and what are the pin count details?
The INA121UA is available in an 8-pin SOIC (SO-8) package with a 1.27mm pin pitch. The compact surface-mount form factor makes it easy to integrate into space-constrained PCB layouts.
What are common applications for the INA121UA?
The INA121UA is used in bridge transducer amplification, medical ECG/EEG front ends, industrial data acquisition, strain gauge interfaces, thermocouple signal conditioning, and any application requiring high-precision differential signal amplification with high-impedance sources.
What are good substitutes or alternatives for the INA121UA?
Compatible alternatives include the INA128 (lower noise, bipolar input), INA129 (rail-to-rail output), AD8221 from Analog Devices (lower noise floor), and INA818 (lower power, rail-to-rail). Selection depends on noise budget, supply voltage, and input impedance requirements.
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About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $8.0600 | $8.06 |
| 3+ | $7.1100 | $21.33 |
| 10+ | $6.1300 | $61.30 |
| 60+ | $3.3582 | $201.49 |
| 78+ | $3.2463 | $253.21 |
| 104+ | $2.9104 | $302.68 |
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