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HomeProductsIntegrated Circuits (ICs)Linear - Amplifiers - Instrumentation, OP Amps, Buffer AmpsOPA657N/250G4
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OPA657N/250G4 - Texas Instruments

Manufacturer Part Number
OPA657N/250G4
Manufacturer
Texas Instruments
Allelco Part Number
32D-OPA657N/250G4
Warranty
1 Year Allelco Warranty - Find out more
Stock Status:
9,990 pcs available, New & Original
Parts Description
IC OPAMP VFB 1 CIRCUIT SOT23-5
Package
SOT-23-5
Data sheet
-
RoHs Status
ROHS3 Compliant
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In stock: 9990
  • Unit Price: $9.439
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Quantity Unit Price Ext. Price
1+ $9.439 $9.44
250+ $3.653 $913.25
500+ $3.525 $1,762.50
1000+ $3.461 $3,461.00
The above prices does not include taxes and freight rates, which will be calculated on the order pages.

Specifications

OPA657N/250G4 Tech Specifications
Texas Instruments - OPA657N/250G4 technical specifications, attributes, parameters and parts with similar specifications to Texas Instruments - OPA657N/250G4

Product Attribute Attribute Value
Manufacturer Texas Instruments
Voltage - Supply Span (Min) 8 V
Voltage - Supply Span (Max) 12 V
Voltage - Input Offset 250 µV
Supplier Device Package SOT-23-5
Slew Rate 700V/µs
Series -
Package / Case SC-74A, SOT-753
Package Tape & Reel (TR)
Output Type -
Product Attribute Attribute Value
Operating Temperature -40°C ~ 85°C
Number of Circuits 1
Mounting Type Surface Mount
Gain Bandwidth Product 1.6 GHz
Current - Supply 14mA
Current - Output / Channel 70 mA
Current - Input Bias 2 pA
Base Product Number OPA657
Amplifier Type Voltage Feedback
-3db Bandwidth 350 MHz

Environmental & Export Classifications

ATTRIBUTE DESCRIPTION
RoHs Status ROHS3 Compliant
Moisture Sensitivity Level (MSL) 2 (1 Year)
REACH Status REACH Unaffected
ECCN EAR99

Frequently Asked Questions(FAQ)

How does the OPA657N/250G4 compare to other voltage feedback amplifiers in terms of slew rate and bandwidth when driving high-capacitive loads?
The OPA657N/250G4 delivers a slew rate of 700 V/µs and a -3 dB bandwidth of 350 MHz, which places it among high-speed amplifiers capable of handling demanding signal transitions. However, when driving large capacitive loads, its phase margin may degrade significantly due to internal compensation designed for stability at unity-gain. Compared to amplifiers with current-feedback architectures, the OPA657 maintains superior linearity and lower distortion up to its gain-bandwidth product of 1.6 GHz, but may exhibit reduced output swing under heavy capacitive loading. In practice, for capacitive loads exceeding 200 pF, external isolation resistors or small series output capacitors are typically required to prevent instability—this behavior is consistent across similar voltage feedback op-amps from TI and competitors.
What is the recommended supply voltage range and how does it affect performance in a ±5V single-supply design using the OPA657N/250G4?
The OPA657N/250G4 supports a supply span from 8 V to 12 V, meaning it is optimized for dual-supply operation within that range. Attempting to use it in a ±5V system (total supply span of 10 V) would fall below the minimum specified span of 8 V, potentially compromising input common-mode range, output swing headroom, and overall dynamic performance. While some marginal functionality might occur near the boundary, reliable operation is not guaranteed. For single-supply designs requiring lower voltages, alternative amplifiers with wider supply compatibility should be considered unless the application can tolerate higher power consumption and heat dissipation associated with higher-voltage operation.
Can the OPA657N/250G4 be used in precision DC applications given its input offset voltage and bias current specifications?
Although the OPA657N/250G4 has an input offset voltage of 250 µV and an input bias current of 2 pA, its architecture and compensation scheme are tailored for high-speed rather than ultra-precision DC performance. While this offset level is acceptable for many analog front-end tasks, it introduces measurable error in gain stages below approximately 100x without trimming or calibration. Additionally, temperature drift characteristics—not explicitly detailed in the base parameters—are likely non-negligible over industrial temperature ranges. Therefore, while feasible for certain buffered sensor interfaces or active filters where speed dominates accuracy needs, it is generally outperformed by dedicated precision op-amps like the OPA189 or OPA2188 in true DC-critical systems.
Is the OPA657N/250G4 suitable for RF signal conditioning in wideband communication systems?
With a gain-bandwidth product of 1.6 GHz and a -3 dB bandwidth of 350 MHz, the OPA657N/250G4 offers sufficient bandwidth for many intermediate-frequency (IF) and RF pre-amplification tasks. However, its voltage-feedback topology introduces trade-offs in noise figure, input impedance flatness, and group delay variation across frequency. At higher frequencies, parasitic capacitances and package resonances become significant; the SOT-23-5 packaging limits RF layout optimization compared to larger packages with better grounding. In practice, this device may function adequately in moderate-gain RF chains up to ~2 GHz, but for coherent detection or low-noise receive paths, a specialized RF amplifier or LNA would provide superior linearity and phase coherence.
How does the output current capability of the OPA657N/250G4 impact its use in driving ADC input buffers?
The OPA657N/250G4 provides up to 70 mA of output current per channel, which is more than adequate for most 12- to 16-bit successive approximation register (SAR) ADCs that require fast settling and moderate drive strength. When buffering a high-resolution ADC input, this current enables rapid charging of load capacitance (e.g., 10–50 pF), reducing settling time and minimizing aperture jitter. However, the amplifier’s internal compensation limits closed-loop bandwidth under unity-gain configurations, so achieving maximum ADC throughput may require careful attention to feedback resistor values and PCB parasitics. Compared to rail-to-rail output devices, the OPA657N/250G4 maintains consistent performance near supply rails only within its specified span, making it well-suited for buffered sampling in data acquisition systems requiring both speed and moderate resolution.
What are the thermal implications of operating the OPA657N/250G4 continuously at full supply voltage in a compact SOT-23-5 package?
Operating continuously at 12 V supply draws approximately 14 mA quiescent current, resulting in about 168 mW of power dissipation in steady state. In the small SOT-23-5 package, this leads to a junction-to-ambient thermal resistance (θJA) typically around 200°C/W, implying a temperature rise of roughly 34°C above ambient at room conditions. While the device is rated from -40°C to 85°C, sustained high-power operation could approach derated limits, especially in poorly ventilated enclosures or crowded PCBs. Thermal crowding with nearby components may exacerbate self-heating effects. Therefore, although brief transients or pulsed operation are manageable, continuous full-load usage demands careful layout planning—including adequate copper pour, vias, or airflow—to maintain junction temperatures well below 125°C.
How does the Moisture Sensitivity Level (MSL) of 2 for the OPA657N/250G4 influence reflow soldering procedures?
The MSL rating of 2 indicates that the OPA657N/250G4 requires protection from moisture absorption prior to reflow, with a floor life of up to one year if stored properly. Exposure to humid environments before assembly can lead to popcorning during thermal stress, damaging the semiconductor die or bond wires. Standard IPC/JEDEC guidelines mandate baking or humidity-controlled storage if the component exceeds the allowable exposure window based on floor time and environmental conditions. This precaution applies regardless of package size, but is particularly critical for fine-pitch surface-mount devices like the SOT-23-5. Proper handling ensures reliability during automated production and reduces field failure risks associated with moisture-induced delamination.
Can the OPA657N/250G4 replace MAX4104EUK+T in a legacy design, and what key differences should engineers consider?
While the MAX4104EUK+T is listed as a substitute for the OPA657N/250G4, direct substitution requires verification of several critical parameters. The MAX4104 is a current-feedback amplifier with a much higher slew rate (typically >1000 V/µs) but a lower bandwidth (often <100 MHz), making it unsuitable for broadband voltage-feedback applications. Additionally, the MAX4104 operates at lower supply voltages (typically ±2.5 V to ±5 V), whereas the OPA657N/250G4 needs at least ±4 V (8 V total). Output current, input offset, and noise characteristics also differ significantly. Therefore, while both serve high-speed roles, they target different design constraints—speed vs. power efficiency, or voltage vs. current feedback—and cannot be universally interchanged without redesign considerations.
What layout precautions are essential when routing signals to or from the OPA657N/250G4 in a mixed-signal PCB?
Given the OPA657N/250G4’s high bandwidth and low input bias current, sensitive traces must avoid coupling noise from digital aggressors such as clock lines or switching regulators. Keep signal paths short, use controlled impedance where necessary, and minimize trace lengths to reduce parasitic capacitance and inductance. Ground planes should be uninterrupted beneath the amplifier, and decoupling capacitors (typically 0.1 µF ceramic placed within 5 mm of the V+ and V− pins) are critical to suppress supply noise at GHz frequencies. Since the amplifier is unconditionally stable at unity gain but sensitive to capacitive loads, any added capacitance on the output should be evaluated for stability margins using simulation tools. Proper shielding and guard rings around input pins further reduce leakage currents, especially important due to the 2 pA bias current level.
Does the OPA657N/250G4 support single-supply operation, and if so, what input/output limitations arise?
The OPA657N/250G4 does not natively support single-supply operation within standard configurations. Its specified supply range spans 8 V to 12 V, implying dual-supply use (±4 V to ±6 V). Attempting to operate it on a single positive rail (e.g., +12 V) without modifying biasing will restrict the input common-mode range and likely cause output clipping, as the inputs and outputs must remain within the supply rails. Some users attempt to bias inputs to mid-supply via resistors, but this increases power consumption and may degrade CMRR or introduce offset errors. For single-supply compatibility, TI recommends alternative parts like the OPA656 or OPA657 variants with extended rail-to-rail capabilities, though even those have trade-offs in speed and linearity at low supply voltages.
How does the input bias current of 2 pA in the OPA657N/250G4 affect high-impedance sensor interface designs?
The extremely low 2 pA input bias current of the OPA657N/250G4 makes it suitable for interfacing with piezoelectric sensors, photodiodes, or thermistors where leakage currents must be minimized. In high-impedance nodes (e.g., 1 MΩ source impedance), even nanoampere-level leakage creates measurable voltage drops, but picoampere currents result in microvolt-scale offsets—acceptable in many cases. However, long trace lengths or contaminated PCBs can elevate parasitic leakage beyond spec, degrading accuracy. Capacitive coupling between input traces and ground planes may also induce displacement currents that mimic real signals. Therefore, while the device excels in preserving weak analog signals, layout discipline is paramount to leverage its inherent low-leakage advantage fully.
What role does the internal compensation play in the stability of the OPA657N/250G4 when configured with resistive feedback networks?
The OPA657N/250G4 features internal frequency compensation optimized for unity-gain stability, ensuring oscillation-free operation in typical closed-loop gains. This compensation sets a dominant pole that rolls off gain before secondary poles dominate the response. However, in high-gain configurations (e.g., ×100), the phase margin improves, enhancing transient behavior. Conversely, adding excessive capacitance to the feedback path or output can introduce new poles that interact negatively with the existing compensation, leading to peaking or ringing. Designers must verify stability using AC analysis or step-response testing, particularly in filter topologies like Sallen-Key or multiple-feedback bands, where stray capacitance and resistor tolerances compound phase shifts. Conservative feedback resistor selection and minimal trace length help preserve intended compensation behavior.
Is the OPA657N/250G4 RoHS3 compliant, and how does this affect global manufacturing compliance?
Yes, the OPA657N/250G4 is RoHS3 compliant, meaning it meets all current European Union directives regarding hazardous substance restrictions, including lead, mercury, cadmium, hexavalent chromium, PBB, PBDE, and four phthalates (DEHP, BBP, DBP, DIBP). This certification ensures the component can be legally manufactured and distributed in RoHS-regulated markets without additional exemptions. Combined with its REACH unaffected status and EAR99 classification, the part presents minimal regulatory risk for commercial electronics producers worldwide. Engineers sourcing this device can confidently integrate it into products destined for consumer, industrial, or medical applications without concerns about export controls or material bans.
How does the operating temperature range (-40°C to 85°C) limit the OPA657N/250G4’s deployment in automotive or outdoor environments?
The OPA657N/250G4 is rated from -40°C to 85°C, which aligns with industrial-grade requirements but falls short of automotive AEC-Q100 qualifications. In outdoor or high-temperature industrial settings, ambient temperatures can exceed 85°C, causing junction temperatures to rise rapidly under power dissipation. Even modest quiescent power (e.g., 14 mA at 12 V) generates 168 mW, leading to significant self-heating in compact packages. Without active cooling, the device may throttle performance or fail prematurely. For applications where temperatures regularly approach or exceed 85°C, derating calculations must account for both ambient and self-heating effects. Alternative solutions include selecting higher-temperature-rated parts, improving thermal management, or relocating heat-generating circuitry away from sensitive analog sections.
What is the significance of the base product number OPA657 in relation to the specific variant OPA657N/250G4?
The base product number OPA657 refers to a family of high-speed voltage feedback amplifiers from Texas Instruments, with various suffixes indicating packaging, grade, and performance bins. The variant OPA657N/250G4 includes the "N" denoting SOT-23-5 packaging and the "/250G4" specifying a particular offset voltage bin—here, 250 µV maximum input offset. This binning allows customers to select parts meeting tighter offset specifications without paying for broader tolerance. Other variants might offer lower offset (e.g., /100G4) or different temperature grades. Understanding the base number helps identify compatible alternatives and ensures consistency across design revisions, while the specific suffix guarantees parameter adherence for precision-critical implementations.
How does the gain bandwidth product of 1.6 GHz influence closed-loop gain selection in video or communications systems using the OPA657N/250G4?
The 1.6 GHz gain bandwidth product (GBW) defines the theoretical upper limit for closed-loop gain-bandwidth combinations. For example, at a gain of 10, the usable bandwidth is approximately GBW/gain = 160 MHz; at gain = 100, it drops to 16 MHz. In video systems requiring 100 MHz bandwidth, the maximum achievable gain is limited to ~16x. This constraint shapes front-end architecture: higher gains necessitate narrower bandwidths, potentially forcing trade-offs in signal fidelity or anti-aliasing requirements. Engineers must plan feedback networks accordingly, often opting for lower gains with additional filtering rather than pushing into bandwidth-limited regimes. Real-world parasitics further reduce effective GBW, so margin should be included in initial calculations.
Can the OPA657N/250G4 be safely used in redundant or paralleled amplifier configurations for increased output current?
Paralleling multiple OPA657N/250G4 units to increase output current is generally discouraged due to mismatch in offset, gain, and output impedance between channels. Without precise matching, circulating currents can develop under load, causing uneven power dissipation and potential thermal runaway in one or more devices. Even with current-sharing techniques, the lack of built-in isolation makes such configurations unreliable. Instead, dedicated multi-channel amplifiers or external current-boosting stages with feedback control are preferred for high-current applications. The OPA657N/250G4’s 70 mA capability already exceeds typical signal chain demands, making parallelization unnecessary and counterproductive from a stability and reliability standpoint.
What are the implications of the SC-74A/SOT-753 package designation for mechanical and thermal performance of the OPA657N/250G4?
The SC-74A (also known as SOT-753) package is a miniature surface-mount format closely related to the SOT-23-5 but with slightly different pinout and thermal characteristics. Despite sharing a similar footprint, the SC-74A typically exhibits higher θJA than the standard SOT-23-5 due to smaller die attach area and less efficient heat spreading. This impacts thermal performance under continuous power, requiring closer attention to PCB copper area and airflow. Mechanically, its small size benefits space-constrained designs but complicates hand soldering and inspection. Pinout differences mean direct socket or footprint reuse with SOT-23-5 may not be possible, necessitating board redesigns. Always consult the latest TI package drawing for accurate dimensions and thermal metrics when integrating the OPA657N/250G4 into production layouts.

Parts with Similar Specifications

The three parts on the right have similar specifications to Texas Instruments OPA657N/250G4

Product Attribute OPA657NB/250G4 OPA657NB/250 OPA657N/250 OPA657NB/3KG4
Part Number OPA657NB/250G4 OPA657NB/250 OPA657N/250 OPA657NB/3KG4
Manufacturer Texas Instruments Texas Instruments Texas Instruments Texas Instruments
Amplifier Type - - - -
Mounting Type - Surface Mount Through Hole Surface Mount
Gain Bandwidth Product - - - -
Voltage - Supply Span (Max) - - - -
Base Product Number - DAC34H84 MAX500 ADS62P42
Package / Case - 196-LFBGA 16-DIP (0.300', 7.62mm) 64-VFQFN Exposed Pad
Package - Tape & Reel (TR) Tube Tape & Reel (TR)
Operating Temperature - -40°C ~ 85°C 0°C ~ 70°C -40°C ~ 85°C
Slew Rate - - - -
Current - Input Bias - - - -
Output Type - Current - Unbuffered Voltage - Buffered -
Supplier Device Package - 196-NFBGA (12x12) 16-PDIP 64-VQFN (9x9)
Current - Output / Channel - - - -
-3db Bandwidth - - - -
Current - Supply - - - -
Voltage - Input Offset - - - -
Series - - - -
Voltage - Supply Span (Min) - - - -
Number of Circuits - - - -

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Customer Reviews

Evaluation: 10 Articles

  • Nath***rooks
    Jun 11, 2026

    Installed this power component in a converter board. Output remained stable under different load conditions and thermal performance was better than expected.

  • Dani***alkerTech
    Jun 1, 2026

    Product works, but setup took more effort than expected. Once configured the MCU ran reliably, although documentation support felt older compared with newer platforms. Fine for maintenance projects.

  • Yuki***aka88
    May 26, 2026

    信号通信プロジェクトでこのRS-485トランシーバーを使用しました。設置は簡単で、長距離ケーブルでも通信は安定していました。消費電力も、以前使用していたものより低くなっています。

  • Stev***aker
    May 20, 2026

    Solid diode for power rectification. Works well in switching circuits.

  • Bran***Lewis
    May 11, 2026

    Compact FPGA with good performance. Suitable for basic signal processing tasks.

  • Oliv***arris
    May 7, 2026

    Reliable I/O expander. Works well in embedded control applications.

  • Jess***Jones
    Apr 17, 2026

    It offers good value for the price, and the specifications match the description. I’ve been using it for two days with no issues, and I’ll definitely buy it again if I need it in the future.

  • Mich***Smith
    Apr 17, 2026

    Shipping was on time, the component pins are neatly aligned, and I tested 10 of them with a multimeter—all readings were within the specified range. Highly recommended.

  • Aman***arris
    Apr 3, 2026

    It was great—the entire process, from placing the order to receiving the package, went very smoothly. The components were consistent, the price was fair, and I had a very pleasant shopping experience.

  • Mike***nch
    Apr 3, 2026

    Better than expected! The resistance and capacitance readings were spot-on, and it passed the test on the first try. The service was reliable, and the packaging was thoughtful—I highly recommend it.

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OPA657N/250G4 Image

OPA657N/250G4

Texas Instruments
32D-OPA657N/250G4

Want a better price? Add to Cart and Submit RFQ now, we'll contact you immediately.

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