AD8475 Precision, Selectable Gain, Fully Differential Funnel Amp

The AD8475 is a fully differential, attenuating amplifier with integrated precision gain resistors. It provides precision attenuation (by 0.4 or 0.8), common-mode level shifting, and single-ended-to-differential conversion along with input overvoltage protection. Power dissipation on a single 5 V supply is only 16 mW.

The AD8475 is a simple to use, fully integrated precision gain block, designed to process signal levels of up to ±10 V on a single supply. It provides a complete interface to make industrial level signals directly compatible with the differential input ranges of low voltage, high performance 16-bit or 18-bit single-supply successive approximation (SAR) analog-to-digital converters (ADCs).

The AD8475 comes with two standard pin-selectable gain options: 0.4 and 0.8. The gain of the part is set by driving the input pin corresponding to the appropriate gain.

The AD8475 also provides overvoltage protection from large industrial input voltages up to ±15 V while operating on a single 5 V supply. The VOCM pin adjusts the output voltage common mode for precision level shifting, to match the ADC’s input range and maximize dynamic range. The AD8475 works extremely well with SAR, Σ-Δ, and pipeline converters. The high current output stage of the part allows it to drive the switched capacitor front-end circuits of many ADCs with minimal error.

Unlike many differential drivers in the market, the AD8475 is a high precision amplifier. With 500 μV maximum output offset, 10 nV/√Hz output noise, and −112 dB THD + N, the AD8475 pairs well with high accuracy converters. Considering its low power consumption and high precision, the slew-enhanced AD8475 has excellent speed, settling to 18-bit precision for 4 MSPS acquisition.

The AD8475 is available in a space-saving 10-lead MSOP package. It is fully specified over the −40°C to +85°C temperature range.

Applications

Features and Benefits
  • Precision attenuation: G = 0.4, G = 0.8
  • Fully differential or single-ended input/output
  • Differential output designed to drive precision ADCs
    Drives switched capacitor and Σ-Δ ADCs
    Rail-to-rail output
  • VOCM pin adjusts output common mode
  • Robust over-voltage protection up to ±15V (VS = +5 V)
  • Single supply: 3V to 10V
  • Dual supplies: ±1.5V to ±5V
  • High performance
    Suited for driving 18-bit converter up to 4 MSPS
    10 nV/√Hz output noise
    3 ppm/°C gain drift
    See data sheet for additional features
  • Amplifiers
    Aerospace and Defense
    • Solutions
    SPICE Models
    Reference Designs
    Data Sheets
    Documentnote
    AD8475: Precision, Selectable Gain, Fully Differential Funnel Amplifier Data Sheet (Rev. C)PDF 1627 kB
    Application Notes
    Documentnote
    AN-1363: Meeting Biasing Requirements of Externally Biased RF/Microwave Amplifiers with Active Bias Controllers (Rev. 0)PDF 804.11 K
    AN-1264: Precision Signal Conditioning for High Resolution Industrial Applications (Rev. 0)PDF 469 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    AD8475ACPZ-R7 Production16 ld LFCSP (3x3mm, 1.5mm exposed pad)REEL 1500-40 to 85C2.391.99Y
    AD8475ACPZ-RL Production16 ld LFCSP (3x3mm, 1.5mm exposed pad)REEL 5000-40 to 85C2.391.99Y
    AD8475ACPZ-WP Production16 ld LFCSP (3x3mm, 1.5mm exposed pad)REEL 50-40 to 85C2.391.99Y
    AD8475ARMZ Production10 ld MSOPOTH 50-40 to 85C2.391.99Y
    AD8475ARMZ-R7 Production10 ld MSOPREEL 1000-40 to 85C2.391.99Y
    AD8475ARMZ-RL Production10 ld MSOPREEL 3000-40 to 85C2.391.99Y
    AD8475BRMZ Production10 ld MSOPOTH 50-40 to 85C3.32.75Y
    AD8475BRMZ-R7 Production10 ld MSOPREEL 1000-40 to 85C3.32.75Y
    AD8475BRMZ-RL Production10 ld MSOPREEL 3000-40 to 85C3.32.75Y
    Evaluation Boards
    Part NumberDescriptionPriceRoHS
    AD8475-EVALZEvaluation Board20.98Y
    Reference Materials
    AD8475: Precision, Selectable Gain, Fully Differential Funnel Amplifier Data Sheet (Rev. C) ad8475
    AD8475:精密、可选增益、全差分漏斗放大器 数据手册 (Rev. B) ad8475
    AD8475 SPICE Macro-Model ad8475
    CN0310 设计和集成文件 ad8475
    CN0269 设计和集成文件 adg5208
    CN0251 设计和集成文件 adg1409
    CN0240 设计和集成文件 ad8475
    CN0180 设计和集成文件 ad8475
    CN0292 Design & Integration Files adg1204
    CN0272 设计和集成文件 ad8475
    AN-1363: 利用有源偏置控制器满足外部偏置射频/微波放大器的偏置要求 (Rev. 0) hmc8120
    AN-1363: Meeting Biasing Requirements of Externally Biased RF/Microwave Amplifiers with Active Bias Controllers (Rev. 0) hmc8120
    AN-1264: Precision Signal Conditioning for High Resolution Industrial Applications (Rev. 0) ad7195
    AN-1264: 高分辨率工业应用中的精密信号调理 (Rev. 0) ad8475
    SAR ADC & Driver Quick-Match Guide ad7476
    CN0345: 集成PGIA、用于工业级信号的低功耗、多通道数据采集系统 adg1207
    CN0292:用于工业电平信号的完全隔离、鲁棒、4通道、多路复用数据采集系统 adg1204
    CN0310:24位、250 kSPS单电源数据采集系统 ad8475
    CN-0251:24位、4.7 Hz、4通道模拟数据采集系统 adg1409
    CN0269:18位、1.33 MSPS、16通道数据采集系统 adg5208
    CN-0272:具有暗电流补偿功能的2 MHz带宽PIN光电二极管前置放大器 ad8475
    CN0240: 具有270 V共模抑制性能的双向隔离式高端电流检测模块 ad8475
    CN-0180: Precision Single-Supply Differential ADC Driver for... ad7982