OPA124-W - 1.5 MHz Low-Noise Precision Op Amp | Texas Instruments
MPN: OPA124-W ✗ End of LifeOPA124-W Overview
An operational amplifier is an analog integrated circuit that uses differential feedback to amplify the difference between two input voltages. The OPA124-W belongs to the operational amplifier, analog amplifier, and signal-conditioning IC hierarchy, with a JFET-input architecture suited to high-impedance sources. Compared with bipolar-input precision amplifiers, the very low input bias current helps preserve source accuracy in sensors, transducers, and laboratory instrumentation.
Key characteristics include a 1.5 MHz gain-bandwidth product, 1.6 V/us slew rate, 10 V to 36 V operating supply range, and approximately 2.5 mA typical supply current. The low-noise precision architecture makes the device useful for signal-chain conditioning, current-to-voltage conversion, instrumentation, and low-level analog measurement. The available verified data does not state the exact package for OPA124-W, so the package and its physical dimensions must be confirmed from the manufacturer ordering information before layout or replacement decisions.
Typical use cases include conditioning outputs from high-impedance sensors, amplifying small differential signals, precision filter stages, and general-purpose analog instrumentation. In an instrumentation application, the amplifier's low bias current reduces loading of the source, while its 1.5 MHz bandwidth supports signal paths with moderate frequency content. The 10 V to 36 V supply range also provides flexibility for laboratory and industrial equipment operating from elevated rails.
Designers should verify the exact pinout, package, common-mode range, offset voltage, noise density, and output-current limits against the current Texas Instruments datasheet before production release. The available distributor information confirms that OPA124-W is an amplifier product and that the OPA124 family is a low-noise precision Difet operational amplifier. This page combines verified product facts, sourcing links, engineering-oriented application guidance, and the limits of the available substitute data.
Drop-in alternatives for OPA124-W — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
OPA124UA
✅ Drop-In📋 Reference alternative (not in catalog)
OPA140AID
✅ Drop-In📋 Reference alternative (not in catalog)
OPA145
✅ Drop-In📋 Reference alternative (not in catalog)
OPA124-W Maximum Ratings & Electrical Characteristics
| Number of Circuits | 1 circuit |
| Input Type | JFET input |
| Architecture | Difet precision operational amplifier |
| Gain-Bandwidth Product | 1.5 MHz |
| Slew Rate | 1.6 V/us |
| Supply Voltage Range | 10 V to 36 V |
| Typical Supply Current | 2.5 mA |
| Maximum Input Bias Current | 1 pA |
| Product Type | Single-circuit operational amplifier |
| Application Class | General-purpose precision amplifier |
| Noise Class | Low-noise operational amplifier |
| RoHS Status | unknown |
| REACH Status | unknown |
| AEC-Q100 Qualification | not_applicable |
OPA124-W standard Pin Configuration Guide
Pin configuration for OPA124-W (standard package). This analog component features input, output, and power supply pins. Refer to the manufacturer datasheet for offset null, compensation, and enable pin configurations. Ideal for signal conditioning and amplifier circuits.
No detailed pinout data available for OPA124-W.
Refer to the datasheet for full pin configuration.
Typical Applications
OPA124-W is suitable for 6 applications: High-Impedance Sensor Signal Conditioning, Precision Current-to-Voltage Conversion, Laboratory Instrumentation Front End, Low-Level Differential Amplifier, Precision Active Filter, Industrial Analog Measurement Interface.
High-Impedance Sensor Signal Conditioning
OPA124-W fits high-impedance sensor signal conditioning because its verified maximum input bias current is 1 pA, which limits the error current drawn from the source. The amplifier's 1.5 MHz gain-bandwidth product and 1.6 V/us slew rate are sufficient for low- and moderate-bandwidth transducer signals. Place it in a non-inverting or differential conditioning stage, then confirm input offset voltage, common-mode range, and output swing against the sensor excitation and signal amplitude. The low bias current is especially valuable where the sensor output impedance is high enough that bias-current-induced voltage error could obscure the measured quantity.
Recommended
Precision Current-to-Voltage Conversion
OPA124-W is appropriate for precision current-to-voltage conversion when the source is a photodiode, electrochemical sensor, or other high-impedance current source. The verified 1 pA maximum input bias current reduces unwanted output generated by bias current through a transimpedance resistor. Its 1.5 MHz gain-bandwidth product supports moderate-bandwidth transimpedance designs, while the 1.6 V/us slew rate helps preserve large-signal response. The exact common-mode input range, output swing, and stability configuration must be verified from the manufacturer datasheet before setting resistor and capacitor values.
Recommended
Laboratory Instrumentation Front End
OPA124-W can serve as the front-end amplifier in laboratory instrumentation where low input bias current and low-noise behavior help preserve source integrity. The verified 10 V to 36 V operating supply range supports elevated-rail analog systems, and the approximately 2.5 mA typical supply current is manageable in multi-channel instruments. Its 1.5 MHz gain-bandwidth product is adequate for many precision measurement paths but not high-bandwidth instrumentation. Layout should use short feedback routes, clean grounding, and supply bypassing, while the amplifier's offset and noise characteristics should be included in the total measurement uncertainty budget.
Recommended
Low-Level Differential Amplifier
OPA124-W is suitable for low-level differential amplification when source bias current must remain small and the signal bandwidth is moderate. Its verified 1 pA maximum input bias current reduces loading of both differential inputs, while the 1.5 MHz gain-bandwidth product and 1.6 V/us slew rate support accurate amplification of slow or intermediate-frequency signals. A resistor-matched differential stage can use the amplifier for common-mode rejection and gain, although mismatch and resistor noise may dominate ultimate accuracy. Confirm input offset voltage, common-mode limits, and output capability before finalizing the gain and operating-point calculation.
Recommended
Precision Active Filter
OPA124-W can be used in precision active-filter stages driven by high-impedance networks or sensors. The JFET input's verified 1 pA maximum input bias current minimizes error in the filter time constant, and the 1.5 MHz gain-bandwidth product provides useful bandwidth for low-frequency precision filtering. The 1.6 V/us slew rate also helps limit large-signal distortion in filters handling moderate signal amplitudes. Component tolerances, the amplifier's finite gain and output limits, and the intended stopband attenuation should be modeled together. Because the exact OPA124-W package and pinout are not present in the supplied data, they must be confirmed before PCB implementation.
Recommended
Industrial Analog Measurement Interface
OPA124-W fits industrial analog measurement interfaces that operate from elevated supply rails and require low input bias current. Its verified 10 V to 36 V supply range is useful in 24 V-oriented industrial systems when the amplifier's absolute maximum ratings permit the selected rail. The 1 pA maximum input bias current protects high-impedance transducer interfaces, while the 1.5 MHz bandwidth handles measurement signals with moderate frequency content. Designers should include supply tolerance, transients, input common-mode limits, and offset error in system qualification. The amplifier should be paired with suitable input protection and filtering for industrial transients.
Recommended
Recommended Products Summary
Engineering reference data for OPA124-W — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | OPA124UA | OPA140AID | OPA145 |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Offset-Control Function | OPA124-family offset-control functionality | OPA124-family functionality; exact configuration requires confirmation | May not include the OPA124 offset-control pin | May not include the OPA124 offset-control pin |
Key Differentiators
- Very low input bias current for high-impedance sources (vs OPA140AID)
- Established same-family sourcing path (vs OPA145)
- Moderate precision bandwidth with a defined slew rate (vs OPA124UA)
Design Notes
Keep the OPA124-W feedback loop physically short and use a compact, low-inductance connection around the amplifier pins. For precision gain stages, route the inverting input and feedback components away from noisy digital, clock, and switching-supply paths. The exact pin numbers and exposed connections are not available in the supplied verified data, so the first schematic and PCB review should use the current Texas Instruments package drawing and pin table rather than assumptions based on generic SOIC layouts.
Use supply bypassing close to the amplifier and preserve adequate headroom across the verified 10 V to 36 V operating range. The typical supply current is approximately 2.5 mA, but total rail current also depends on the external circuit. Check whether the selected production variant supports the intended positive or dual supply configuration, and do not treat the operating range as permission to exceed absolute maximum ratings. Add input protection or filtering where the source or industrial supply can present transients.
Do not assume that every 8-pin amplifier is a drop-in replacement for the OPA124-W. TI specifically noted that some alternatives can share the 8-pin SOIC footprint while having higher input bias current and lacking the OPA124 offset-control function; another forum excerpt mentioned a substrate pin on pin 8 of one OPA124 variant. Confirm the exact target package, substrate connection, offset-control implementation, bias current, offset voltage, common-mode range, and stability before substitution.
Compliance Information
The supplied verified excerpts do not state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status for OPA124-W. Compliance values remain unknown rather than being assumed.
