THS4021ID - 290 MHz Low-Noise Op Amp | Texas Instruments
Référence : THS4021ID ✓ ActifTHS4021ID Présentation
A voltage-feedback amplifier is an active analog signal-conditioning device that uses negative feedback to control gain and bandwidth. The THS4021 belongs to the operational-amplifier hierarchy, combining low input-referred voltage noise with high-speed closed-loop operation. This combination makes it suitable for communications receivers, imaging systems, instrumentation, test equipment, and other circuits that must preserve small signals at high frequencies.
According to the Texas Instruments THS4021 product page and manufacturer datasheet, principal features include 2 GHz gain-bandwidth product, 290 MHz closed-loop bandwidth, 470 V/µs slew rate, and 30 ns settling time to 0.1%. The device is a single amplifier rather than a dual amplifier, reducing channel count where only one high-speed signal path is required. Its low voltage noise is particularly important when amplification occurs before a downstream converter or measurement stage.
The amplifier uses a voltage-feedback architecture, which provides direct control of gain through external feedback components when configured for inverting, non-inverting, and summing operation. The high gain-bandwidth product supports operation over a broad frequency range, while the 290 MHz closed-loop bandwidth defines its practical response in the gain configuration used by the design. The 470 V/µs slew rate helps preserve large-amplitude, high-frequency waveforms without excessive distortion.
Typical uses include low-noise communications front ends, imaging and photodetector signal paths, high-speed instrumentation, analog test equipment, and clock or data conversion interfaces. The device can also serve in broadband transimpedance and active-filter stages where low noise and rapid settling are both valuable. Actual signal bandwidth depends on gain, feedback impedance, output loading, trace impedance, and the bandwidth of surrounding components.
PCB implementation should use short, controlled-impedance connections and minimize parasitic capacitance at the high-impedance input node. Place feedback components close to the amplifier, provide a stable low-impedance supply reference, and follow the manufacturer pinout and layout guidance. Termination, decoupling, and probe measurements must be treated as part of the complete high-frequency circuit rather than as isolated component choices.
This product page combines the manufacturer specifications, package details, verified source links, application guidance, and a conservative drop-in cross-reference assessment. It also distinguishes a confirmed same-package option from alternatives that lack sufficient evidence for PCB-level substitution, helping designers compare options without treating electrically similar amplifiers as guaranteed pin-to-pin replacements.
Alternatives de remplacement direct pour THS4021ID — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
THS4021CD
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
OPA846ID
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
THS4021ID Valeurs maximales et caractéristiques électriques
| Amplifier Type | Single-channel voltage-feedback amplifier |
| Gain-Bandwidth Product | 2 GHz |
| Closed-Loop Bandwidth | 290 MHz |
| Slew Rate | 470 V/µs |
| Settling Time | 30 ns to 0.1% |
| Input Noise Type | Ultra-low voltage noise |
| Number of Channels | 1 channel |
| Boîtier | 8-pin SOIC, 3.90 mm width |
| Type de montage | Surface mount |
Guide de configuration des broches du THS4021ID 8-pin soic, 3.90 mm width
Configuration des broches du THS4021ID (boîtier 8-pin soic, 3.90 mm width). Ce composant analogique comporte des broches d'entrée, de sortie et d'alimentation. Consultez la fiche technique du fabricant pour les configurations des broches d'annulation d'offset, de compensation et d'activation. Idéal pour le conditionnement de signaux et les circuits amplificateurs.
Aucune donnée de brochage détaillée disponible pour THS4021ID.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
THS4021ID convient pour 6 applications: Communications Front End, Imaging and Photodetector Signal Chain, High-Speed Instrumentation, Analog Test and Measurement, Clock and Data Interface Conditioning, Broadband Active Filtering.
Communications Front End
The THS4021ID fits low-level communications front ends because it combines ultra-low voltage noise with a 2 GHz gain-bandwidth product and 290 MHz closed-loop bandwidth. Place it in a gain stage ahead of a mixer, ADC, or receiver block when small signals must be amplified without adding excessive broadband noise. The 470 V/µs slew rate also supports higher-frequency waveforms. Board implementation must preserve high-frequency behavior with short feedback paths, low-impedance supply routing, controlled-impedance interconnects, and careful grounding around the input and output nodes.
Recommandé
Imaging and Photodetector Signal Chain
The THS4021ID is suitable for imaging systems that amplify small photodetector or video-related signals while requiring fast response. Its 290 MHz closed-loop bandwidth supports wide-band signal conditioning, while the 30 ns settling time to 0.1% is valuable in pulse and sampled imaging circuits. Ultra-low voltage noise helps preserve weak signals early in the chain. For transimpedance applications, evaluate photodiode capacitance, feedback resistance, feedback capacitance, bias current, and loop stability together because nominal bandwidth alone does not define the complete response.
Recommandé
High-Speed Instrumentation
The THS4021ID can serve in high-speed instrumentation where sensor outputs or test signals must be conditioned with low noise and accurate settling. Its 2 GHz gain-bandwidth product provides design headroom for multiple closed-loop gain settings, while 470 V/µs slew rate improves large-signal response. Use the amplifier around the sensor rather than after unnecessary gain stages so that system noise is not amplified ahead of it. The enclosure, grounding, input filtering, and reference circuitry should be designed so that EMI and temperature drift do not obscure the amplifier's intrinsic performance.
Recommandé
Analog Test and Measurement
The THS4021ID is appropriate for analog test and measurement systems requiring rapid settling and low input-referred voltage noise. The 30 ns settling time to 0.1% supports measurement circuits that need to reach a defined accuracy point quickly, and the 290 MHz closed-loop bandwidth supports high-frequency stimulus and response. At the board level, controlled impedances and short routes are essential because otherwise transmission-line effects, parasitic inductance, and probe capacitance can dominate. Include output loading, cable or fixture delay, input termination, and sample timing in system-level error budgets.
Recommandé
Clock and Data Interface Conditioning
The THS4021ID can condition low-amplitude clock or data signals when the circuit requires very low voltage noise and rapid transition capability. Its 2 GHz gain-bandwidth product and 470 V/µs slew rate make it suitable for edge shaping, buffering, and short-distance high-speed interface stages. The 8-pin SOIC package allows a conventional surface-mount implementation, but signal integrity still depends on continuous reference planes, correct impedance, minimized stubs, and deliberate termination. Validate amplitude, timing, overshoot, and ringing at the receiver rather than assuming the amplifier alone guarantees interface compliance.
Recommandé
Broadband Active Filtering
The THS4021ID can be used in active-filter and frequency-response circuits where the selected closed-loop gain must coexist with low noise and high speed. The 290 MHz closed-loop bandwidth provides a useful upper reference when designing gain and compensation networks, and the 470 V/µs slew rate helps preserve large-amplitude signals near the bandwidth limit. Place feedback and compensation parts close to the amplifier and verify stability with the actual source and load impedances. High-Q filters and very low closed-loop gains are particularly sensitive to parasitic capacitance and excess loop gain.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour THS4021ID — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | THS4021CD | OPA846ID |
|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC |
| Amplifier Architecture | Single-channel voltage-feedback amplifier | Single-channel voltage-feedback amplifier | Voltage-feedback amplifier |
| Number of Channels | 1 channel | 1 channel | 1 channel |
Principaux différenciateurs
- Combines high speed with ultra-low voltage noise (vs OPA846ID)
- Single-channel design in an 8-pin SOIC (vs THS4022)
- Same-package orderable family option (vs THS4021CD)
Notes de conception
Route the high-impedance input and feedback nodes as short as possible, and place feedback resistors and compensation capacitors directly beside the amplifier pins. A long input trace can add parasitic capacitance that changes bandwidth, noise, and stability. Keep the ground return continuous beneath the device and use a solid reference plane for controlled-impedance interconnects.
Treat every connection above the amplifier's intended bandwidth as a transmission-line problem when trace length is significant. Use the manufacturer's recommended source and load impedances, terminate the interface intentionally, and avoid unneeded test pads or stubs. Verify eye amplitude, edge rate, overshoot, and settling at the receiver because a fast amplifier does not guarantee a compliant interface by itself.
Do not select a substitute from bandwidth alone. Before approving THS4021CD or OPA846ID, compare the exact pin functions, supply limits, output swing, input common-mode range, noise, stability, shutdown behavior, and exposed temperature grade. An 8-pin SOIC outline is necessary but not sufficient for a drop-in replacement.
Informations de conformité
Environmental and qualification status must be confirmed for the exact THS4021ID orderable code through current Texas Instruments documentation.