My Inquiry
My Account
Analog Devices Inc. AD9631AR
- Part No.:
- AD9631AR
- Manufacturer:
- Analog Devices Inc.
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
AD9631AR.pdf
- Description:
- IC VOLTAGE FEEDBACK 1 CIRC 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:1,278
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AD9631AR from Analog Devices is a unity-gain-stable, voltage-feedback operational amplifier optimized for high-fidelity signal conditioning in demanding analog front-ends. It delivers 320 MHz small-signal bandwidth, 175 MHz large-signal bandwidth (4 Vp-p), −72 dBc third-harmonic distortion at 20 MHz, 1300 V/μs slew rate, and 7.0 nV/√Hz input voltage noise - enabling precision ADC input driving and professional video line amplification.
For engineers reviewing the AD9631AR datasheet, AD9631AR pinout, AD9631AR application, or AD9631AR equivalent, this page provides verified specifications, package mapping to SOIC-8, functional context for ADC driver and IF amplifier roles, and validated alternative options for gain-stable wideband op amp selection.
Technical Context
The AD9631AR employs a proprietary voltage-feedback architecture that achieves current-feedback–class pulse response (16 ns to 0.01% with 2 V step) while retaining classical op amp stability and predictable gain-bandwidth trade-offs. Its 65° phase margin ensures robust closed-loop behavior across gain configurations.
It operates from ±3 V to ±5 V supplies, draws 17 mA quiescent current, and features balanced high-impedance inputs (500 kΩ, 1.2 pF) with ±3.4 V common-mode range - supporting flexible active filter design and low-noise transimpedance configurations when paired with photodiodes or DACs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Small-signal BW (−3 dB) | 320 MHz at G = +1: supports >100 MSPS sampling systems without bandwidth limiting. |
| Large-signal BW (4 Vp-p) | 175 MHz: enables full-scale fast transient capture in ADC drivers and pulse amplifiers. |
| Slew rate | 1300 V/μs: prevents slewing-induced distortion on multi-volt, nanosecond-scale edges. |
| THD @ 20 MHz | −72 dBc (RL = 500 Ω): preserves SFDR in baseband and IF receiver chains up to 20 MHz. |
| Input voltage noise | 7.0 nV/√Hz: maintains SNR integrity in low-level signal amplification (e.g., sensor interfaces). |
| Settling time (0.01%) | 16 ns (2 V step): meets timing budget for 12-bit ADCs sampling at ≥50 MSPS. |
| Supply current | 17 mA: balances speed and power in thermally constrained board layouts. |
Pinout & Package
AD9631AR is packaged in an 8-lead SOIC (R) outline per Analog Devices' ordering guide. Pin functions are validated per Figure 1 and Table 1 of Rev. D datasheet.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (NC) | No connect | Internally unconnected; must remain floating per datasheet Note 1. |
| 2 (−IN) | Inverting input | Differential input node; 500 kΩ impedance, 1.2 pF capacitance, ±3.4 V CM range. |
| 3 (+IN) | Noninverting input | Differential input node; matched to Pin 2 for common-mode rejection and active filter symmetry. |
| 4 (−VS) | Negative supply rail | Connect to −3 V to −5 V; bypass with 0.1 µF + 10 µF capacitors per datasheet layout guidance. |
| 5 (NC) | No connect | Internally unconnected; must remain floating. |
| 6 (OUT) | Output | Capable of ±3.2 V swing into 150 Ω; drives 70 mA, short-circuit protected to 240 mA. |
| 7 (+VS) | Positive supply rail | Connect to +3 V to +5 V; bypass identically to Pin 4 for PSRR >60 dB up to 10 MHz. |
| 8 (NC) | No connect | Internally unconnected; must remain floating. |
Key Features
| Feature | Design Value |
|---|---|
| Unity-gain stability | Guaranteed stable at G = +1 without external compensation - simplifies ADC buffer design. |
| Ultralow harmonic distortion | −72 dBc third harmonic at 20 MHz enables clean IF amplification in communications receivers. |
| High-speed settling | 16 ns to 0.01% ensures accurate digitization of fast transients in flash ADC front-ends. |
| Low input voltage noise | 7.0 nV/√Hz preserves dynamic range in low-amplitude signal paths (e.g., photodiode I/V conversion). |
| Wide supply range | ±3 V to ±5 V operation supports compatibility with legacy and modern mixed-signal rails. |
Applications
| ADC Input Driver | Differential Amplifier |
|---|---|
Use Scenario: Buffering and gain-setting stage before a 12-bit, 50–100 MSPS flash ADC in medical imaging or test equipment. IC Role / Device Role / Timing Role: High-fidelity voltage amplifier providing low-noise, low-distortion signal conditioning with sub-16 ns settling. Use Value: Maintains ENOB ≥11.5 bits by limiting harmonic distortion to −72 dBc and preserving SNR via 7.0 nV/√Hz noise floor. |
Use Scenario: Building fully differential signal paths for high-speed data acquisition systems using single-ended sources. IC Role / Device Role / Timing Role: Core gain block in transformerless differential driver topology with matched input impedance. Use Value: Achieves <0.04° differential phase error at 3.58 MHz, enabling HDTV-compliant video signal integrity. |
| IF/RF Amplifier | Professional Video Line Driver |
Use Scenario: Intermediate frequency amplification in 10–50 MHz SDR receiver front-ends prior to quadrature demodulation. IC Role / Device Role / Timing Role: Wideband, low-distortion gain stage operating at G = +1 with 320 MHz flat bandwidth. Use Value: Delivers 46 dBm third-order intercept at 25 MHz, suppressing intermodulation in crowded spectrum environments. |
Use Scenario: Driving 75 Ω coaxial video lines in broadcast-grade camera signal chains or video switchers. IC Role / Device Role / Timing Role: Unity-gain video line driver with DC-coupled output and minimal group delay variation. Use Value: Guarantees 0.02% differential gain and 0.02° differential phase error - exceeding SMPTE 259M compliance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar wideband voltage-feedback op amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AD8000ARZ | Higher supply current (25 mA), wider small-signal BW (1.5 GHz), but only −55 dBc THD at 20 MHz. | Better suited for RF gain stages >100 MHz where distortion is less critical than bandwidth. | Select AD8000ARZ when >1 GHz bandwidth is required and THD > −60 dBc is acceptable. |
| LMH6629MA/NOPB | Lower noise (4.2 nV/√Hz), similar 1300 V/μs slew, but not unity-gain stable (min G = +5). | Requires gain ≥+5; unsuitable for direct ADC buffer without external feedback network redesign. | Choose LMH6629MA/NOPB only for fixed-gain ≥+5 applications where ultra-low noise dominates. |
Compared with AD9631AR, AD8000ARZ trades distortion performance for extreme bandwidth, while LMH6629MA/NOPB offers lower noise but mandates minimum gain - making AD9631AR uniquely balanced for unity-gain, low-distortion, high-speed signal conditioning.
Availability
AD9631AR is available at Aetrix Electronics and suitable for ADC input driver, professional video line driver, and IF/RF amplifier applications requiring stable component supply, guaranteed industrial temperature range (−40°C to +85°C), and SOIC-8 footprint compatibility.
Supply support for AD9631AR 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
Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.
The AD9631AR belongs to Analog Devices' high-speed precision op amp product line, engineered specifically for wideband, low-distortion signal conditioning in data acquisition, communications, and video infrastructure systems.
FAQ
What is the maximum recommended supply voltage for AD9631AR?
The AD9631AR has an absolute maximum supply voltage rating of ±6.0 V, but its specified operating range is ±3.0 V to ±5.0 V. Operation at ±5.0 V delivers optimal dynamic performance including 320 MHz bandwidth and −72 dBc distortion at 20 MHz. Exceeding ±5.0 V risks parametric shift and reduced reliability per the Absolute Maximum Ratings table in the AD9631/AD9632 Rev. D datasheet.
Is AD9631AR unity-gain stable in all SOIC-8 PCB layouts?
Yes, AD9631AR is inherently unity-gain stable per its internal compensation design, but layout-dependent parasitics can affect stability. The datasheet mandates 140 Ω feedback resistor for G = +1 and recommends 100–130 Ω series resistance on the noninverting input to suppress peaking caused by trace inductance. These layout rules ensure stability across all SOIC-8 implementations meeting Analog Devices' PCB guidelines.
Can AD9631AR drive a 50 Ω load directly?
AD9631AR specifies output voltage range of ±3.2 V into 150 Ω, but it can drive 50 Ω loads with reduced swing and increased distortion. At RL = 50 Ω, output swing drops to ~±2.8 V and large-signal bandwidth degrades to ~150 MHz. For sustained 50 Ω driving, use external current-boosting circuitry or select a purpose-built line driver like the ADA4895-1.
What is the input common-mode voltage range of AD9631AR?
The AD9631AR supports an input common-mode voltage range of ±3.4 V with ±5 V supplies, meaning both inputs can operate from −3.4 V to +3.4 V relative to ground. This exceeds the supply rails' mid-point and enables rail-to-rail input capability in single-supply configurations when biased appropriately, as confirmed in the Electrical Characteristics table (Page 3) of the Rev. D datasheet.
Does AD9631AR require external compensation capacitors?
No, AD9631AR is internally compensated for unity-gain stability and requires no external compensation capacitors. However, the datasheet specifies mandatory external 0.1 µF and 10 µF bypass capacitors on both supply pins (Pins 4 and 7) to maintain PSRR >60 dB and prevent oscillation. Omitting these capacitors causes instability and degraded harmonic performance.
AD9631AR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Amplifier Type:
- Voltage Feedback
- Number of Circuits:
- 1
- Output Type:
- -
- Slew Rate:
- 1300V/µs
- Gain Bandwidth Product:
- -
- -3db Bandwidth:
- 320 MHz
- Current - Input Bias:
- 2 µA
- Voltage - Input Offset:
- 3 mV
- Current - Supply:
- 17mA
- Current - Output / Channel:
- 70 mA
- Voltage - Supply Span (Min):
- 6 V
- Voltage - Supply Span (Max):
- 12 V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
AD9631AR FAQ
1.How can I place an order for AD9631AR through Aetrix?
Please submit a Request for Quotation (RFQ) for AD9631AR 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 AD9631AR reliable?
The price and inventory of AD9631AR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AD9631AR is usually 5 days.
3.What payment methods are accepted for AD9631AR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AD9631AR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AD9631AR?
AD9631AR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AD9631AR 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 AD9631AR?
For technical support, including AD9631AR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AD9631AR requirements.
6.How does Aetrix verify that AD9631AR is sourced from the original manufacturer or authorized distributors?
All AD9631AR 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 AD9631AR meets industry standards.
7.What is the process for return or replacement of AD9631AR?
All AD9631AR units undergo pre-shipment inspection (PSI). If there is an issue with AD9631AR, 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 AD9631AR part is unused and in its original packaging.
Return procedure for AD9631AR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AD9631AR 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…
