OPA211ID - 1.1nV/Hz Precision Op Amp 80MHz SOIC-8 | TI
MPN: OPA211ID ✓ Hoạt độngOPA211ID Tóm tắt
An operational amplifier (op amp) is a high-gain voltage amplifier with differential inputs and a single-ended output, a fundamental building block of analog signal chains. Precision op amps such as the OPA211 sit within the amplifier hierarchy: amplifier > operational amplifier > precision op amp, characterized by low offset, low noise, and high open-loop gain. They are essential in instrumentation, medical equipment, and test systems where signal accuracy is critical.
Key features include the 1.1 nV/√Hz input-referred noise density - among the lowest available for a precision op amp - plus a gain-bandwidth product of 80 MHz and 20 V/µs slew rate for high-speed signals. The rail-to-rail output maximizes dynamic range in low-supply designs. DC accuracy is strong with 50 µV typical offset voltage and 60 nA input bias current, and total harmonic distortion plus noise is a very low 0.000015%.
Technically, the OPA211 uses a bipolar input stage with laser trimming to minimize offset and drift. The class-AB output stage provides low distortion and solid capacitive-drive capability. Single (OPA211) and dual (OPA2211) versions exist, with shutdown options on single-channel family members, packaged in SON-8 (3x3 mm), VSSOP-8, and SOIC-8.
Typical applications include low-noise audio preamplifiers, precision instrumentation front ends, active filters, and data-acquisition stages driving high-resolution ADCs such as the ADS1262. The 80 MHz bandwidth also suits photodiode transimpedance amplifiers and RF/IF signal chains.
Design tip: place 0.1 µF ceramic decoupling capacitors close to the supply pins, and respect the input common-mode range to avoid phase reversal. For a second channel, the OPA2211 shares the same performance in one package. Prices as of 2026-08-30.
Bộ thay thế dễ dàng lắp đặt cho OPA211ID — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với OPA211ID (cùng hình factor và footprint) — khác nhau ở Input Bias Current, Output Type, Package, Slew Rate.
OPA1611ID
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
OPA211AID
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
OPA828IDR
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →AD797ARZ
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
LT1028CS8
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
OPA211ID Tỷ lệ tối đa & tính chất điện
| Độ dày tiếng ồn | 1.1 nV/rtHz |
| Gain-Bandwidth Product | 80 MHz |
| Slew Rate | 20 V/us |
| Điện áp yên tĩnh | 3.6 mA per amplifier |
| Offset Voltage | 50 uV typical |
| Input Bias Current | 60 nA |
| THD+N | 0.000015% |
| Kiểu đầu ra | Rail-to-Rail Output |
| Stability | Unity-Gain Stable |
| Kênh | 1 |
| Nhiệt độ hoạt động | -40C to +125C |
| Hộp | 8-SOIC (D) |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
Cấu hình chân OPA211ID
| Chân 1 | TRIM/NC — Offset trim / no connect per package option |
| Chân 2 | -IN — Inverting input |
| Chân 3 | +IN — Non-inverting input |
| Chân 4 | V- — Negative supply |
| Chân 5 | NC — No connect |
| Chân 6 | OUT — Output (rail-to-rail) |
| Chân 7 | V+ — Positive supply |
| Chân 8 | NC/V+ — No connect or positive supply per package option |
Ứng dụng tiêu biểu
OPA211ID phù hợp cho 6 Áp dụngs: Low-Noise Audio Preamplifier, Precision Data Acquisition Front End, Photodiode Transimpedance Amplifier, Active Filter and Signal Conditioning, Precision Instrumentation and Test Equipment, RF/IF and Wideband Signal Chains.
Low-Noise Audio Preamplifier
The OPA211's 1.1 nV/√Hz noise and 0.000015% THD+N make it excellent for microphone preamps and line stages where noise floor directly limits dynamic range. Placed as a gain stage between a balanced input and an audio ADC, its rail-to-rail output maximizes headroom on 5V single supplies. Unlike audio-optimized parts, it also provides 80 MHz bandwidth for ultrasonic extension, though the bipolar input's 60 nA bias current requires impedance matching on high-source-resistance inputs.
Được đề xuất
Precision Data Acquisition Front End
In data acquisition, the OPA211 amplifies small sensor signals before digitization, using its 50 µV typical offset and 1.1 nV/√Hz noise to preserve low-level resolution. Configured as a gain-of-10 amplifier before a 24-bit ADC, its unity-gain stability and 80 MHz GBW settle quickly, reducing acquisition dead time. A low-pass R-C filter at the ADC input plus 0.1 µF decoupling capacitors at the supply pins keeps the rail clean, per the TI datasheet recommendation for noisy or high-impedance supplies.
Được đề xuất
Photodiode Transimpedance Amplifier
The OPA211's 80 MHz gain-bandwidth product supports fast photodiode TIA designs for optical receivers and instrumentation. With feedback resistors in the 10 kOhm to 100 kOhm range, the closed-loop bandwidth remains in the MHz region, and the 1.1 nV/√Hz input noise limits TIA output noise. Because the bipolar input carries 60 nA bias current, designs with very high photodiode impedance should evaluate the FET-input OPA828, while standard optical links benefit from the OPA211's speed and low voltage noise.
Được đề xuất
Active Filter and Signal Conditioning
The OPA211 works well in multi-feedback and Sallen-Key active filters up to several MHz, where its 80 MHz GBW ensures the filter's Q and corner frequency stay accurate. The 20 V/µs slew rate handles large-signal filter inputs without slewing distortion, and the rail-to-rail output allows the largest possible signal swing. Placing 0.1 µF plus 1 µF decoupling near each supply pin prevents the high bandwidth from coupling supply noise into the filter passband, a pitfall TI's datasheet explicitly warns about.
Được đề xuất
Precision Instrumentation and Test Equipment
In bench instruments and industrial measurement equipment, the OPA211 serves as a low-noise buffer or gain stage for bridge sensors and signal conditioning chains. Its -40C to +125C industrial temperature specification supports harsh environments, while 1.1 nV/√Hz noise preserves measurement resolution at microvolt signal levels. Typical deployment: a gain-of-100 stage ahead of a precision ADC or scope front end; the 60 nA bias current must be balanced by matched source impedances to limit offset error in high-impedance probes.
Được đề xuất
RF/IF and Wideband Signal Chains
The OPA211's 80 MHz bandwidth and 20 V/µs slew rate suit IF amplification and wideband buffering in communications receivers. Its 1.1 nV/√Hz voltage noise contributes minimally to system noise figure when driving 50-ohm-terminated IF stages. Placed after a mixer or ahead of a wideband ADC, the amplifier's class-AB output stage drives moderate loads with 0.000015% THD+N, preserving signal purity. Series resistors at the output help isolate capacitive loads and maintain stability at low closed-loop gains.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho OPA211ID — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | OPA1611ID | OPA211AID | OPA828IDR | AD797ARZ | LT1028CS8 |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices | Analog Devices |
| Noise Density | 1.1 nV/rtHz | 1.1 nV/rtHz class | 1.1 nV/rtHz | 3.3 nV/rtHz | ~0.9 nV/rtHz | ~0.85 nV/rtHz |
| Quiescent Current | 3.6 mA | ~3.6 mA | 3.6 mA | 4.8 mA | Higher (~8 mA class) | Higher (~10 mA class) |
| Gain-Bandwidth | 80 MHz | 40 MHz class | 80 MHz | 33 MHz class | 110 MHz class | 75 MHz class |
| Rail-to-Rail Output | Yes | Yes | Yes | Yes | No | No |
| Input Bias Current | 60 nA | 60 nA class (bipolar) | 60 nA | pA class (FET) | 250 nA class | 25 nA class |
| Offset Voltage (typ) | 50 uV | 50 uV class | Lower (precision grade) | 45 uV class | 25 uV class | 10 uV class |
Bảo phân biệt quan trọng
- Lowest noise per unit current in its class (vsAD797ARZ)
- Rail-to-rail output for maximum dynamic range (vsLT1028CS8)
- Higher bandwidth than audio-optimized sibling (vsOPA1611ID)
Ghi chú thiết kế
Decouple both supply pins with 0.1 uF ceramic capacitors placed within 2 mm of the pins, plus a 2.2 uF bulk capacitor per supply rail. TI's OPAx211 datasheet explicitly warns that noisy or high-impedance supplies require decoupling close to the device pins; the 80 MHz bandwidth can otherwise couple supply noise directly into the output.
The bipolar input has 60 nA bias current; on high-impedance sources this creates offset error (60 nA x source resistance). Match source impedances seen by both inputs to cancel bias effects via bias-current cancellation. Also respect the input common-mode range to avoid phase reversal or degraded CMRR near the rails.
At closed-loop gains below 5, capacitive loads above roughly 20-50 pF can degrade phase margin; add a series isolation resistor (10-50 ohm) at the output when driving long cables or ADC input capacitance. For ADC driving, follow the datasheet typical application with an R-C charge kickback filter sized to the ADC sampling rate.
Thông tin tuân thủ
RoHS compliant per DigiKey/TI product listing. Other compliance attributes not stated in provided data.
