AD8429BRZ - 1nV/√Hz Ultra-Low Noise In-Amp | Analog Devices
料号： AD8429BRZ ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $10.43 | $10.43 |
| 10 | $9.55 | $95.50 |
| 100 | $8.12 | $812.00 |
| 500 | $7.28 | $3,640.00 |
| 1,000 | $6.85 | $6,850.00 |
AD8429BRZ 概述
An instrumentation amplifier (in-amp) is a type of differential amplifier that amplifies the difference between two input signals while rejecting common-mode voltages. It is a specialized variant of the operational amplifier (op-amp) family, optimized for precision measurement applications where high common-mode rejection ratio (CMRR) and low noise are critical. In-amps are widely used in medical instrumentation, industrial process control, and precision data acquisition systems.
Key features of the AD8429BRZ include a minimum CMRR of 90 dB at gain of 1, a maximum input offset voltage of 50 µV, and a maximum gain accuracy of 0.02% at gain of 1. It offers excellent AC specifications with 80 dB CMRR up to 5 kHz, a bandwidth of 15 MHz at gain of 1, and a slew rate of 22 V/µs. The total harmonic distortion (THD) is -130 dBc at 1 kHz, ensuring high signal fidelity.
The AD8429 uses a three-op-amp topology with a precision laser-trimmed resistor network, achieving high accuracy and stability over temperature. The gain is set by a single external resistor, allowing gains from 1 to 1000. The reference pin (REF) enables level shifting for single-supply operation, and the device includes ESD protection on all pins.
Typical applications include medical instrumentation (ECG, EEG), industrial process control, precision data acquisition, and transducer signal conditioning. The ultralow noise and high CMRR make it suitable for measuring microvolt-level signals in noisy environments.
When designing with the AD8429BRZ, ensure proper supply decoupling with 0.1 µF capacitors close to the supply pins. The REF pin should be driven with a low-impedance source (<1 Ω) for best performance. The gain resistor should be placed close to the device to minimize parasitic capacitance.
直接替换替代料： AD8429BRZ ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： AD8429BRZ （相同外形与封装尺寸） ——差异在于 Operating Temperature Range, Slew Rate.
快速对比工具——选择替代料号进行并排对比：
AD8429ARZ
✅ 直接替换✓ 有现货
$5.5 / 个
查看数据手册 →AD8429BRZ-R7
✅ 直接替换📋 参考替代料（不在目录中）
AD8221ARZ
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$3.29 / 个
查看数据手册 →AD8228ARZ
✅ 直接替换📋 参考替代料（不在目录中）
INA128UA
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
AD8429BRZ 最大额定值与电气特性
| Input Noise Voltage Density | 1 nV/√Hz |
| Output Noise Voltage Density | 45 nV/√Hz |
| CMRR (Minimum, G=1) | 90 dB |
| Input Offset Voltage (Maximum) | 50 µV |
| Gain Accuracy (Maximum, G=1) | 0.02% |
| CMRR to 5 kHz (G=1) | 80 dB |
| Bandwidth (G=1) | 15 MHz |
| Bandwidth (G=100) | 1.2 MHz |
| Slew Rate | 22 V/µs |
| THD (1 kHz, G=1) | -130 dBc |
| Supply Voltage Range | ±4 V to ±18 V |
| 工作温度范围 | -40°C to +125°C |
| 封装 | 8-SOIC |
| 安装类型 | Surface Mount |
| Number of Circuits | 1 |
AD8429BRZ 引脚配置
| 引脚 1 | RG — Gain setting resistor connection |
| 引脚 2 | -IN — Inverting input |
| 引脚 3 | +IN — Non-inverting input |
| 引脚 4 | -VS — Negative supply |
| 引脚 5 | REF — Reference voltage for output level shifting |
| 引脚 6 | OUT — Output |
| 引脚 7 | +VS — Positive supply |
| 引脚 8 | RG — Gain setting resistor connection |
典型应用
AD8429BRZ 适用于 6 应用s: Medical Instrumentation (ECG/EEG), Industrial Process Control, Precision Data Acquisition, Transducer Signal Conditioning, Audio Test and Measurement, Vibration Monitoring.
Medical Instrumentation (ECG/EEG)
The AD8429BRZ's ultralow input noise of 1 nV/√Hz and high CMRR of 90 dB minimum at G=1 make it ideal for amplifying microvolt-level biopotential signals. In ECG systems, it rejects 50/60 Hz common-mode interference from the body and power lines, ensuring clean signal acquisition. The wide bandwidth of 15 MHz at G=1 supports high-resolution QRS detection. Its -40°C to +125°C range allows use in portable and clinical devices. The REF pin enables level shifting for single-supply ADCs, simplifying interface to digital processors.
推荐
Industrial Process Control
In industrial process control, the AD8429BRZ accurately conditions signals from pressure, temperature, and flow sensors. Its high CMRR of 90 dB at G=1 rejects common-mode noise from long cable runs and motor drives. The low input offset voltage of 50 µV max ensures precise measurement of small sensor outputs. The wide supply range of ±4 V to ±18 V accommodates standard industrial rails. The device's robustness over -40°C to +125°C makes it suitable for harsh factory environments. Its 15 MHz bandwidth allows fast response to process changes.
推荐
Precision Data Acquisition
The AD8429BRZ is ideal for precision data acquisition systems requiring high resolution and low noise. Its 1 nV/√Hz input noise and 0.02% gain accuracy at G=1 ensure accurate digitization of small signals. The device's high bandwidth of 15 MHz supports high-speed sampling, while the low THD of -130 dBc preserves signal fidelity. The REF pin allows easy interface to single-supply ADCs, and the wide supply range provides flexibility in system design. Its small 8-SOIC package saves board space in multi-channel systems.
推荐
Transducer Signal Conditioning
The AD8429BRZ excels in conditioning signals from various transducers, such as strain gauges, thermocouples, and RTDs. Its ultralow noise of 1 nV/√Hz preserves the tiny signal variations from these sensors. The high CMRR rejects common-mode interference from excitation sources and environmental noise. The gain set by a single external resistor allows easy adjustment from 1 to 1000, accommodating different sensor sensitivities. The device's wide temperature range ensures stable performance in varying conditions. Its low offset voltage minimizes measurement error.
推荐
Audio Test and Measurement
The AD8429BRZ's low THD of -130 dBc and wide bandwidth of 15 MHz make it suitable for audio test equipment. It can accurately amplify low-level audio signals without introducing distortion. The high CMRR rejects ground loops and common-mode noise in test setups. The device's low noise ensures that the measurement system does not mask the signal under test. Its small package allows integration into portable test instruments. The REF pin enables output level shifting for single-supply ADCs in digital audio analyzers.
推荐
Vibration Monitoring
In vibration monitoring systems, the AD8429BRZ conditions signals from accelerometers and piezoelectric sensors. Its ultralow noise of 1 nV/√Hz allows detection of small vibrations, while the high CMRR rejects interference from motors and power lines. The wide bandwidth of 15 MHz captures high-frequency vibration components. The device's wide supply range and temperature range make it suitable for industrial monitoring equipment. The gain resistor allows optimization for different sensor sensitivities.
推荐
推荐产品汇总
工程参考数据： AD8429BRZ ——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 | AD8429ARZ | AD8429BRZ-R7 | AD8221ARZ | AD8228ARZ | INA128UA |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Texas Instruments |
| Input Noise Voltage Density | 1 nV/√Hz | 1 nV/√Hz | 1 nV/√Hz | 8 nV/√Hz | 8 nV/√Hz | 8 nV/√Hz |
| CMRR (Min, G=1) | 90 dB | 90 dB | 90 dB | 80 dB | 80 dB | 80 dB |
| Bandwidth (G=1) | 15 MHz | 15 MHz | 15 MHz | 1 MHz | 650 kHz | 200 kHz |
| Input Offset Voltage (Max) | 50 µV | 100 µV | 50 µV | 60 µV | 50 µV | 50 µV |
| Supply Voltage Range | ±4 V to ±18 V | ±4 V to ±18 V | ±4 V to ±18 V | ±2.3 V to ±18 V | ±2.3 V to ±18 V | ±2.25 V to ±18 V |
| Gain Range | 1 to 1000 | 1 to 1000 | 1 to 1000 | 1 to 1000 | Fixed 10 or 100 | 1 to 10000 |
关键差异点
- Ultralow input noise of 1 nV/√Hz （对比 AD8221ARZ)
- High CMRR of 90 dB minimum at G=1 （对比 INA128UA)
- Wide bandwidth of 15 MHz at G=1 （对比 AD8228ARZ)
设计说明
The AD8429BRZ operates from dual supplies of ±4 V to ±18 V. Use low-impedance supply traces and place 0.1 µF ceramic capacitors close to the +VS and -VS pins to decouple high-frequency noise. For best performance, use a 10 µF tantalum capacitor in parallel for bulk decoupling, especially when driving low-impedance loads.
For optimal noise performance, keep the gain-setting resistor (RG) close to the device and use short, direct traces. Avoid routing high-speed digital signals near the input pins to prevent coupling. Use a ground plane under the device to minimize parasitic inductance and provide a low-impedance return path.
The REF pin must be driven with a low-impedance source (<1 Ω) to maintain CMRR and accuracy. Do not exceed the REF pin voltage beyond ±VS by more than 0.3 V, as it is protected by ESD diodes. Ensure the input common-mode voltage stays within the specified range to avoid output saturation.
合规信息
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.
