THS3111CD - 100 MHz Low-Noise Current-Feedback Amp | TI
料号： THS3111CD ✓ 量产中THS3111CD 概述
A current-feedback amplifier is a voltage-feedback amplifier architecture that uses an internal transconductance stage and feedback current to set gain. Its gain-bandwidth behavior differs from that of a conventional operational amplifier: bandwidth generally remains relatively consistent as closed-loop gain increases. This makes the THS3111CD useful in video, communications, instrumentation, and signal-conditioning circuits where accurate pulse reproduction and fast settling are required. The part is also classified as a single current-feedback amplifier rather than a dual or quad device.
Key electrical characteristics include low voltage noise of 3 nV/√Hz, noninverting current noise of 2 pA/√Hz, inverting current noise of 10 pA/√Hz, and high output current drive of 260 mA. The device also provides 68 dB CMRR and an input bias current of 4 µA. Its high-voltage supply range supports larger signal swings and provides more headroom for demanding analog stages. The wide bandwidth and 1300 V/µs slew rate enable the amplifier to process high-frequency signals without the bandwidth collapse commonly associated with voltage-feedback amplifiers in low-gain configurations.
Typical applications include video routing and distribution, communications receivers, high-speed instrumentation, active filters, and general-purpose signal conditioning. In these applications, the THS3111CD is selected when the signal path requires low noise, high output drive, and strong large-signal performance. The 8-pin SOIC package is compatible with conventional surface-mount assembly, while careful attention to grounding, feedback-loop layout, and supply decoupling remains necessary for stable operation.
For layout, place the input, output, feedback, and power-ground connections as close as practical to the device. Use short, low-inductance feedback traces and place supply bypass capacitors near the power pins. Avoid routing sensitive input signals adjacent to high-current output paths, and check the feedback network against the gain and stability requirements in the manufacturer datasheet.
This page provides the core specifications, application guidance, comparison parameters, and design notes needed to evaluate THS3111CD in high-speed analog designs. The complete pin description, recommended application circuit, electrical test conditions, and ordering information should be checked in the Texas Instruments THS3111 datasheet before final schematic and PCB release.
直接替换替代料： THS3111CD ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
THS3111CDRG4
✅ 直接替换📋 参考替代料（不在目录中）
THS3111CDG4
✅ 直接替换📋 参考替代料（不在目录中）
THS3111CD 最大额定值与电气特性
| Product Type | Single current-feedback operational amplifier |
| Amplifier Circuit Count | 1 circuit |
| Nominal Unity-Gain Bandwidth | 100 MHz |
| Wide Bandwidth | 90 MHz |
| High Slew Rate | 1300 V/µs at RL = 8 VPP |
| Supply Voltage Range | ±5 V to ±15 V |
| Voltage Noise | 3 nV/√Hz |
| Noninverting Current Noise | 2 pA/√Hz |
| Inverting Current Noise | 10 pA/√Hz |
| High Output Current Drive | 260 mA |
| Common-Mode Rejection Ratio | 68 dB |
| Input Bias Current | 4 µA |
| 封装 | 8-pin SOIC (D) |
| Terminal Count | 8 terminals |
| Terminal Form | Gull wing |
| Temperature Grade | Commercial |
| 安装类型 | Surface mount |
| Power Dissipation | 1050 mW maximum |
THS3111CD 8-pin soic (d) 引脚配置指南
THS3111CD（8-pin soic (d) 封装）的引脚配置。 该模拟元件具有输入、输出和电源引脚。请参阅制造商数据手册以了解失调调零、补偿和使能引脚配置。适用于信号调理和放大器电路。
暂无详细引脚数据： THS3111CD.
请参阅 数据手册 以查看完整引脚配置。
典型应用
THS3111CD 适用于 6 应用s: High-Speed Video Signal Conditioning, Communications Receiver Front End, Precision Active Filtering, High-Speed Instrumentation Signal Chain, Industrial Data-Acquisition Front End, Audio and Low-Distortion Amplification.
High-Speed Video Signal Conditioning
The THS3111CD fits video conditioning stages that must preserve fast edges while adding low-noise gain. Its 100 MHz nominal unity-gain bandwidth, 90 MHz wide bandwidth, and 1300 V/µs slew rate allow large-amplitude transitions to propagate without the severe slew-rate limitation of many precision amplifiers. The 260 mA output-current capability is useful when driving a terminated video load or a short downstream cable. Designers should use the current-feedback topology from the manufacturer datasheet, maintain short feedback traces, and confirm that the selected closed-loop gain remains stable with the actual source and load impedances.
推荐
Communications Receiver Front End
The THS3111CD is appropriate for communications receiver amplification where low noise and wide bandwidth must coexist. Its 3 nV/√Hz voltage noise supports signal-chain noise control, while the 100 MHz nominal unity-gain bandwidth and 1300 V/µs slew rate provide ample bandwidth for fast transitions. The 68 dB CMRR helps reject common-mode disturbances, although common-mode range and output swing must be checked for the selected supply. Because this is a current-feedback amplifier, the feedback resistors and source impedance should follow the Texas Instruments application guidance rather than conventional voltage-feedback rules.
推荐
Precision Active Filtering
The THS3111CD can implement active filters and frequency-selective analog stages that benefit from its 100 MHz nominal unity-gain bandwidth and high slew rate. The wide bandwidth reduces the gain-bandwidth constraint that can limit precision operational amplifiers at higher closed-loop gain, while the 3 nV/√Hz voltage noise is useful when low-level signals pass through the filter. Current-feedback amplifiers can require different gain and stability checks than voltage-feedback devices, especially around high Q-factor filter nodes. Validate component tolerances, interaction, and peaking by simulating the complete network with the actual source and load models.
推荐
High-Speed Instrumentation Signal Chain
The THS3111CD is useful in instrumentation stages that acquire or condition rapidly changing sensor signals. Its 3 nV/√Hz voltage noise, 100 MHz nominal unity-gain bandwidth, and 1300 V/µs slew rate provide a strong combination of small-signal resolution and large-signal speed. The 260 mA output drive can support downstream buffering when loads are suitably controlled. For sensor interfaces, verify input bias current of 4 µA against the source impedance, examine offset and drift in the full datasheet, and use short feedback paths to preserve the intended high-speed behavior.
推荐
Industrial Data-Acquisition Front End
The THS3111CD can serve as the high-bandwidth input stage of an industrial data-acquisition system, especially when sensor outputs change quickly and must be sampled accurately. Its 90 MHz wide bandwidth and 1300 V/µs slew rate reduce timing distortion, while the 3 nV/√Hz voltage-noise figure supports low-level signal conditioning. The ±5 V to ±15 V supply range permits operation from conventional split analog supplies used in industrial equipment. Confirm input common-mode range, output swing, and ADC drive requirements with the manufacturer electrical characteristics, and decouple each supply pin close to the device.
推荐
Audio and Low-Distortion Amplification
The THS3111CD can be used in audio and low-distortion amplification stages where both noise and transient performance matter. Its 3 nV/√Hz voltage noise provides a low-noise foundation, while the 90 MHz wide bandwidth and 1300 V/µs slew rate reproduce large-signal waveforms with low timing distortion. The high output-current capability of 260 mA is useful for driving moderate loads, although output swing, distortion, and load stability remain important constraints. Use the manufacturer feedback network, keep the layout compact, and evaluate THD and stability in the final load configuration before committing to the design.
推荐
推荐产品汇总
工程参考数据： THS3111CD ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | THS3111CDRG4 | THS3111CDG4 |
|---|---|---|---|
| Package | 8-pin SOIC (D) | 8-pin SOIC (D) | 8-pin SOIC (D) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Amplifier Type | Current-feedback operational amplifier | Current-feedback operational amplifier | Current-feedback operational amplifier |
| Circuit Count | 1 circuit | 1 circuit | 1 circuit |
关键差异点
- High speed with low-noise voltage performance （对比 THS3111CDRG4)
- Large-signal output capability （对比 THS3111CDG4)
- Wide supply range for high-voltage analog stages （对比 THS3111CDRG4)
设计说明
Keep the current-feedback loop physically small and route the feedback network directly between the amplifier output and inverting input. The 100 MHz bandwidth and 1300 V/µs slew rate make trace inductance significant. Use short, continuous feedback traces, place feedback resistors close to the device, and avoid routing the input node beside the output. If the source impedance is non-zero, account for it when selecting the feedback network because it can alter gain and peaking.
Place the supply bypass capacitors immediately adjacent to the THS3111CD power pins and connect the capacitor ground return directly to the device ground pin. Separate noisy switching-current paths from the amplifier supply traces so supply ripple is not injected into the signal path. The device operates across ±5 V to ±15 V; select bypass capacitors and decoupling values that are effective over the signal frequencies of interest, while observing the capacitor voltage rating and the manufacturer’s recommended supply configuration.
Do not design a current-feedback amplifier as though it were a conventional voltage-feedback amplifier. Gain-bandwidth behavior, stability, and the preferred feedback impedance differ, especially at low closed-loop gain. Use the feedback resistor values and source/load assumptions from the manufacturer’s typical application circuits. Also verify output swing, input common-mode range, and output-current capability under the actual load; a wide-band amplifier can still distort or clip if the operating point does not provide sufficient voltage headroom.
For video, communications, or instrumentation inputs, treat the source impedance and cable termination as part of the feedback calculation. Terminate the line appropriately at the receiver or source rather than adding a separate termination that changes the current-feedback operating condition. Simulate gain, peaking, and pulse response with realistic source and load models. The 90 MHz wide bandwidth is valuable only when the surrounding layout and terminations prevent reflections and unintended feedback.
合规信息
The product is identified as a commercial-grade Texas Instruments component, but no explicit RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declaration is included in the cited product and distributor information. AEC-Q100 is not applicable to the stated commercial-grade ordering configuration.
