AD8538ARZ - Precision Auto-Zero Op Amp | Analog Devices
MPN： AD8538ARZ ✓ 啟用中AD8538ARZ 概覽
An auto-zero (or chopper-stabilized) op amp is a type of operational amplifier that continuously corrects its input offset voltage using a nulling technique, achieving near-zero offset and drift. This makes it ideal for precision signal conditioning, sensor interfaces, and instrumentation where offset errors would otherwise degrade accuracy. The AD8538 belongs to the family of precision amplifiers, which are essential building blocks in analog signal chains.
Key features of the AD8538ARZ include a maximum input offset voltage of 13 µV, input offset drift of 0.03 µV/°C, and a low input bias current of 25 pA. The supply current is less than 215 µA maximum per amplifier at 5.0 V, making it suitable for battery-powered and low-power applications. It also offers high gain, CMRR, and PSRR, ensuring accurate amplification in noisy environments.
The AD8538 uses a proprietary auto-zero architecture that eliminates the need for external trimming and maintains precision over the entire operating temperature range of -40°C to +125°C. This architecture provides excellent long-term stability and low 1/f noise, which is critical for DC precision applications.
Typical applications include precision current sensing, thermocouple and RTD signal conditioning, medical instrumentation, and portable battery-powered devices. The low power consumption and small SOIC-8 package make it easy to integrate into space-constrained designs.
When designing with the AD8538ARZ, ensure proper decoupling of the power supply pins with 0.1 µF ceramic capacitors placed close to the device. The input common-mode range extends to the negative rail, but for best performance, keep inputs within the specified common-mode voltage range.
直接替換替代品，適用於 AD8538ARZ — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： AD8538ARZ （相同外形與佔位） — 差異在於 Slew Rate, Gain Bandwidth Product, Input Bias Current, Package, Amplifier Type.
AD8539ARZ
✅ 直接替換聯絡詢價
查看資料表 →AD8538ARZ-REEL7
✅ 直接替換📋 參考替代品（不在目錄中）
AD8538AUJZ-R2
✅ 直接替換📋 參考替代品（不在目錄中）
MCP6V11-E/SN
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
OPA2188AIDR
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
LMP7721MA
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
AD8538ARZ 最大額定值與電氣特性
| Amplifier Type | Auto-Zero (Chopper-Stabilized) |
| Number of Circuits | 1 |
| Supply Voltage - Single | 2.7 V to 5.5 V |
| Supply Voltage - Dual | ±1.35 V to ±2.75 V |
| Input Offset Voltage (Max) | 13 µV |
| Input Offset Drift | 0.03 µV/°C |
| Input Bias Current | 25 pA |
| Supply Current (Max) | 215 µA at 5.0 V |
| Slew Rate | 400 mV/µs |
| 工作溫度範圍 | -40°C to +125°C |
| 封裝 | 8-SOIC (SOIC-8) |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant |
AD8538ARZ 腳位配置
| 腳位 1 | OUT — Output |
| 腳位 2 | -IN — Inverting input |
| 腳位 3 | +IN — Non-inverting input |
| 腳位 4 | V- — Negative supply |
| 腳位 5 | NC — No connect |
| 腳位 6 | NC — No connect |
| 腳位 7 | NC — No connect |
| 腳位 8 | V+ — Positive supply |
典型應用
AD8538ARZ 適用於 6 應用s: Precision Current Sensing, Thermocouple and RTD Signal Conditioning, Medical Instrumentation, Portable Battery-Powered Devices, Industrial Process Control, Test and Measurement Equipment.
Precision Current Sensing
The AD8538ARZ's ultra-low offset voltage of 13 µV and low offset drift of 0.03 µV/°C enable accurate current measurement across shunt resistors. In a typical high-side current sensing circuit, the op amp amplifies the small voltage drop across a shunt, and the auto-zero architecture minimizes offset-induced errors, ensuring precise current monitoring in battery management systems and motor control. The low supply current of 215 µA makes it suitable for always-on sensing in portable devices. For best performance, use a precision shunt resistor and place the op amp close to the sensing element to reduce noise pickup.
推薦
Thermocouple and RTD Signal Conditioning
The AD8538ARZ is ideal for thermocouple and RTD signal conditioning due to its low offset voltage (13 µV max) and low offset drift (0.03 µV/°C). In a thermocouple interface, the op amp amplifies the small Seebeck voltage, and the auto-zero architecture ensures that offset errors do not corrupt the measurement. The low input bias current of 25 pA minimizes loading on high-impedance sensors. The device operates from 2.7 V to 5.5 V, allowing direct battery operation. For cold-junction compensation, pair with a precision temperature sensor and use a low-pass filter to reduce noise.
推薦
Medical Instrumentation
The AD8538ARZ is well-suited for medical instrumentation such as ECG and blood glucose monitors, where precision and low power are critical. Its ultra-low offset voltage of 13 µV ensures accurate signal amplification, while the low supply current of 215 µA extends battery life in portable devices. The auto-zero architecture provides excellent long-term stability, reducing the need for calibration. The small SOIC-8 package allows compact PCB designs. For safety, ensure proper isolation and use medical-grade power supplies.
推薦
Portable Battery-Powered Devices
The AD8538ARZ is ideal for portable battery-powered devices due to its low supply current of less than 215 µA at 5.0 V. It operates from a single supply as low as 2.7 V, making it compatible with Li-ion batteries. The low offset voltage and drift ensure accurate signal processing in applications like portable instrumentation and wearable sensors. The SOIC-8 package is compact, and the device's wide temperature range (-40°C to +125°C) supports outdoor use. To maximize battery life, use power-saving modes and minimize the op amp's quiescent current.
推薦
Industrial Process Control
The AD8538ARZ is suitable for industrial process control applications such as pressure and temperature transmitters, where precision and reliability are essential. Its low offset voltage (13 µV) and low drift (0.03 µV/°C) ensure accurate signal conditioning over a wide temperature range. The device operates from 2.7 V to 5.5 V, allowing use in 3.3 V or 5 V systems. The auto-zero architecture provides long-term stability, reducing maintenance. For harsh environments, consider conformal coating and proper ESD protection.
推薦
Test and Measurement Equipment
The AD8538ARZ is used in test and measurement equipment such as data acquisition systems and precision voltmeters, where accuracy is paramount. Its ultra-low offset voltage of 13 µV and low input bias current of 25 pA minimize measurement errors. The device's high gain and CMRR ensure accurate amplification of small signals in noisy environments. The low supply current is beneficial for portable instruments. For best performance, use precision resistors and proper shielding to reduce noise.
推薦
推薦產品摘要
工程參考資料，適用於 AD8538ARZ — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | AD8539ARZ | MCP6V11-E/SN | OPA2188AIDR |
|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Microchip Technology | Texas Instruments |
| Number of Channels | 1 | 2 | 1 | 2 |
| Input Offset Voltage (Max) | 13 µV | 13 µV | 2 µV | 25 µV |
| Input Bias Current | 25 pA | 25 pA | 1 pA | 150 pA |
| Supply Current (Max) | 215 µA | 215 µA per amp | 300 µA | 475 µA per amp |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.2 V to 5.5 V | 4.5 V to 36 V |
| Slew Rate | 400 mV/µs | 400 mV/µs | 500 mV/µs | 800 mV/µs |
主要差異化特點
- Ultra-low offset voltage of 13 µV max (對比OPA2188AIDR)
- Low supply current of 215 µA max (對比MCP6V11-E/SN)
- Single-channel simplicity (對比AD8539ARZ)
設計說明
The AD8538ARZ operates from a single supply of 2.7 V to 5.5 V or dual supplies of ±1.35 V to ±2.75 V. Ensure the supply voltage is within the specified range to avoid damage. Use a 0.1 µF ceramic capacitor close to the V+ and V- pins for decoupling, as recommended in the datasheet.
For optimal performance, place the AD8538ARZ close to the signal source to minimize trace inductance and noise pickup. Use a ground plane and keep analog traces short. Decouple the power supply pins with 0.1 µF ceramic capacitors placed as close as possible to the device, as per the datasheet layout guidelines.
Avoid exceeding the absolute maximum supply voltage of 5.5 V. The input common-mode range extends to the negative rail, but for best performance, keep inputs within the specified common-mode voltage range. Do not leave unused pins floating; connect NC pins to ground or leave unconnected as per datasheet.
合規資訊
RoHS compliant per Analog Devices product page. AEC-Q100 not applicable for this commercial-grade part.
