My Inquiry
My Account
Texas Instruments OPA657NB/250G4
- Part No.:
- OPA657NB/250G4
- Manufacturer:
- Texas Instruments
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- SC-74A, SOT-753
- Datasheet:
-
OPA657NB/250G4.pdf
- Description:
- IC OPAMP VFB 1 CIRCUIT SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:2,820
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
OPA657NB/250G4 from Texas Instruments is a 1.6-GHz gain-bandwidth, low-noise FET-input voltage-feedback operational amplifier optimized for wideband photodiode transimpedance and high-precision ADC driver applications. It delivers 275 MHz small-signal bandwidth at G = +10, 700 V/µs slew rate, and 4.8 nV/√Hz input voltage noise in a 5-pin SOT-23 package with ±5-V operation.
For engineers reviewing the OPA657NB/250G4 datasheet, OPA657NB/250G4 pinout, OPA657NB/250G4 application, or OPA657NB/250G4 equivalent, this page provides verified specifications, validated pin functions, confirmed photodiode and test-equipment use cases, and two documented alternative parts with technical and application-level distinctions.
Technical Context
The OPA657NB/250G4 uses a decompensated voltage-feedback architecture built on a high-speed complementary bipolar process, enabling stable operation only at gains ≥ +7 V/V. Its JFET input stage delivers ultra-low 2 pA typical input bias current and 0.7 pF differential input capacitance - critical for maintaining bandwidth with high-impedance photodiode sources.
It supports split-supply (±4 V to ±6 V) and single-supply (8 V to 12 V) configurations. In split-supply mode, it achieves symmetrical ±3.5-V output swing into 100 Ω at 25°C, with fast overdrive recovery and 1.3 fA/√Hz input current noise - key for optical time-domain reflectometry (OTDR) and wafer scanning front ends.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Gain-Bandwidth Product | 1.6 GHz - enables >10-MHz signal bandwidth up to G = 160 V/V (44 dB) without stability compromise |
| Small-Signal Bandwidth (G = +10) | 275 MHz - supports high-fidelity amplification of fast optical pulses in photodiode receivers |
| Slew Rate | 700 V/µs - preserves edge integrity for 1-V step signals with <1 ns rise/fall time |
| Input Voltage Noise | 4.8 nV/√Hz - minimizes total input-referred noise in broadband transimpedance designs |
| Input Bias Current | 2 pA (typ) - allows direct interfacing with high-impedance photodiodes without significant DC error |
| Operating Temperature Range | –40°C to +85°C - qualified for industrial embedded and test equipment environments |
| Supply Voltage Range | ±4 V to ±6 V (split) or 8 V to 12 V (single) - flexible lab and system-level power architecture support |
Pinout & Package
OPA657NB/250G4 is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, optimized for high-frequency layout with minimal parasitic inductance and capacitance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OUT) | Amplifier output | Delivers 70 mA sourcing/sinking capability; requires external series resistor for capacitive load stability per Figure 17 |
| 2 (–VS) | Negative power supply | Accepts –4 V to –6 V in split-supply mode; must be decoupled with 0.1 µF ceramic capacitor near pin |
| 3 (IN+) | Noninverting input | High-impedance JFET node (10¹² Ω || 4.5 pF); sensitive to layout-induced coupling and ESD |
| 4 (IN–) | Inverting input | Primary feedback node; low 0.7 pF differential capacitance critical for transimpedance phase margin |
| 5 (+VS) | Positive power supply | Accepts +4 V to +6 V in split-supply mode; shares same decoupling requirements as –VS |
Key Features
| Feature | Design Value |
|---|---|
| Low-input voltage noise | 4.8 nV/√Hz enables sub-picoampere-equivalent input current noise in 10-MHz photodiode applications |
| High output drive | ±70 mA output current supports direct driving of 50 Ω test equipment loads without external buffers |
| Fast overdrive recovery | Sub-20 ns recovery from saturation ensures fidelity in pulsed OTDR and laser diode monitoring systems |
| ESD-protected inputs | ±2000 V HBM rating with internal diode clamps allows robust handling in automated assembly and field service |
| High-grade DC specs option | ±0.1 mV max input offset voltage (high-grade variant) improves DC accuracy in precision ADC front ends |
Applications
| Wideband Photodiode Amplifier | ADC Input Amplifier |
|---|---|
Use Scenario: Amplifying weak, fast current pulses from silicon or InGaAs photodiodes in optical receivers. IC Role / Device Role / Timing Role: Transimpedance amplifier converting photocurrent to voltage with minimal added noise and phase lag. Use Value: 4.8 nV/√Hz input voltage noise and 2 pA bias current enable 1.8 pA/√Hz total input-referred noise over 10 MHz - critical for high-dynamic-range optical detection. |
Use Scenario: Driving SAR or pipeline ADC inputs with full-scale analog signals up to 100 MSPS. IC Role / Device Role / Timing Role: High-fidelity buffer and gain stage ensuring settling within 20 ns to 0.02% with 2-V step. Use Value: 700 V/µs slew rate and 275 MHz bandwidth maintain SNR >70 dB at 5 MHz input - preserving ENOB in high-speed data acquisition. |
| Optical Time Domain Reflectometry (OTDR) | Test and Measurement Front End |
Use Scenario: Detecting backscattered light pulses in fiber-optic cable fault analysis with nanosecond resolution. IC Role / Device Role / Timing Role: Fast-response transimpedance amplifier capturing short-duration return pulses after laser launch. Use Value: Sub-20 ns overdrive recovery and 1.6 GHz GBP allow accurate pulse shape reconstruction for distance-to-fault calculations. |
Use Scenario: Signal conditioning in oscilloscope vertical amplifiers, spectrum analyzer IF stages, and arbitrary waveform generator outputs. IC Role / Device Role / Timing Role: Wideband gain block providing flat frequency response and low harmonic distortion up to 50 MHz. Use Value: –70 dBc 2nd-harmonic distortion at 5 MHz and 2 Vpp enables clean signal generation and measurement without post-processing correction. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-bandwidth FET-input amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| OPA656IDBVR | Unity-gain stable; lower 230 MHz bandwidth and 7 nV/√Hz noise; 290 V/µs slew rate | Preferred for G ≤ +1 applications (e.g., unity-gain buffers), not suitable for G = +7–+160 transimpedance designs | Select OPA656IDBVR only when gain stability at G = +1 is required - OPA657NB/250G4 cannot operate below G = +7 |
| OPA857IRGTR | Dedicated transimpedance amplifier; integrated 5-kΩ/20-kΩ programmable gain; 4.75 GHz GBP but higher 8.9 nV/√Hz noise | Optimized for photodiode current-to-voltage conversion with on-chip gain switching; lacks general-purpose op-amp flexibility | Choose OPA857IRGTR for plug-and-play transimpedance with digital gain control; retain OPA657NB/250G4 for custom high-GBW, low-noise discrete TIA designs |
Compared with OPA656IDBVR and OPA857IRGTR, the OPA657NB/250G4 uniquely balances ultra-high 1.6-GHz GBP, 4.8-nV/√Hz noise, and FET-input impedance - making it the only choice among the three for decompensated, high-gain (>+7), low-noise photodiode amplification requiring >200 MHz closed-loop bandwidth.
Availability
OPA657NB/250G4 is available at Aetrix Electronics and suitable for wideband photodiode amplifiers, high-speed ADC drivers, and optical time-domain reflectometry (OTDR) systems requiring stable component supply across industrial temperature ranges and long production lifecycles.
Supply support for OPA657NB/250G4 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 high-performance op-amps and precision signal-chain solutions.
The OPA657NB/250G4 belongs to TI's OPA high-speed precision amplifier family, designed specifically for optical sensing, test instrumentation, and high-fidelity data acquisition where low noise, wide bandwidth, and JFET input integrity are essential.
FAQ
What is the minimum stable gain for OPA657NB/250G4?
The OPA657NB/250G4 is decompensated and requires a minimum noninverting gain of +7 V/V for stable operation. Attempting to use it at unity gain or G = +2 will cause peaking and potential oscillation. For lower-gain applications, TI recommends the unity-gain stable OPA656IDBVR instead. This gain constraint is inherent to the OPA657NB/250G4's internal compensation and is verified across all production lots and temperature ranges.
Does OPA657NB/250G4 support single-supply operation?
Yes, OPA657NB/250G4 supports single-supply operation from 8 V to 12 V, provided the input and output common-mode voltages remain within the linear operating range (e.g., biased at VCC/2). Its input stage operates correctly with inputs as low as –3.3 V relative to –VS, and its output swings to within 1.8 V of either rail. Single-supply use minimizes –PSRR impact and simplifies power design in portable test equipment.
What is the input capacitance of OPA657NB/250G4 and why does it matter?
The OPA657NB/250G4 has 0.7 pF differential input capacitance and 4.5 pF common-mode input capacitance. This low value is critical in photodiode transimpedance applications: it directly impacts phase margin and bandwidth when combined with feedback resistance. For example, with a 200 kΩ transimpedance resistor, the pole formed by 0.7 pF limits bandwidth unless compensated - making careful PCB layout and feedback network design essential for stability.
How does OPA657NB/250G4 compare to OPA657U/2K5 in performance?
OPA657NB/250G4 and OPA657U/2K5 share identical AC and DC specifications, including 1.6-GHz GBP, 275-MHz bandwidth at G = +10, and 4.8 nV/√Hz noise. The difference lies only in packaging and ordering: OPA657NB/250G4 is the 250-unit tape-and-reel variant in SOT-23 (DBV), while OPA657U/2K5 is the 2,500-unit reel. Both are electrically and thermally identical - no performance trade-offs exist between them.
Can OPA657NB/250G4 drive a 50-Ω load directly?
Yes, OPA657NB/250G4 can drive a 50-Ω load directly, delivering ±3.3 V output swing at 25°C with 70 mA sourcing/sinking capability. However, for optimal stability and flat frequency response, TI recommends adding a 50-Ω series resistor at the output (as shown in Figure 29) to isolate the amplifier from reactive load effects. This configuration maintains 275 MHz bandwidth while preventing peaking caused by PCB trace inductance interacting with the load capacitance.
OPA657NB/250G4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Amplifier Type:
- Voltage Feedback
- Number of Circuits:
- 1
- Output Type:
- -
- Slew Rate:
- 700V/µs
- Gain Bandwidth Product:
- 1.6 GHz
- -3db Bandwidth:
- 350 MHz
- Current - Input Bias:
- 1 pA
- Voltage - Input Offset:
- 100 µV
- Current - Supply:
- 14mA
- Current - Output / Channel:
- 70 mA
- Voltage - Supply Span (Min):
- 8 V
- Voltage - Supply Span (Max):
- 12 V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
OPA657NB/250G4 FAQ
1.How can I place an order for OPA657NB/250G4 through Aetrix?
Please submit a Request for Quotation (RFQ) for OPA657NB/250G4 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for OPA657NB/250G4 reliable?
The price and inventory of OPA657NB/250G4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for OPA657NB/250G4 is usually 5 days.
3.What payment methods are accepted for OPA657NB/250G4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for OPA657NB/250G4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for OPA657NB/250G4?
OPA657NB/250G4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your OPA657NB/250G4 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for OPA657NB/250G4?
For technical support, including OPA657NB/250G4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your OPA657NB/250G4 requirements.
6.How does Aetrix verify that OPA657NB/250G4 is sourced from the original manufacturer or authorized distributors?
All OPA657NB/250G4 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that OPA657NB/250G4 meets industry standards.
7.What is the process for return or replacement of OPA657NB/250G4?
All OPA657NB/250G4 units undergo pre-shipment inspection (PSI). If there is an issue with OPA657NB/250G4, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The OPA657NB/250G4 part is unused and in its original packaging.
Return procedure for OPA657NB/250G4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
OPA657NB/250G4 Tags
-
LM358DT
STMicroelectronics
-
LM358DR
Texas Instruments
-
LM2904DR
Texas Instruments
-
LM358ADR
Texas Instruments
-
LM2904DGKR
Texas Instruments
-
LM324DR
Texas Instruments
-
MCP6006T-E/OT
Microchip Technology
-
MCP6006UT-E/OT
Microchip Technology
-
LM324PWR
Texas Instruments
-
LM2902PWR
Texas Instruments
-
LM2902DR
Texas Instruments
-
LM358P
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
