AD7984BCPZ - 18-Bit 1.33 MSPS SAR ADC | Analog Devices
MPN: AD7984BCPZ ✓ Hoạt độngAD7984BCPZ Tóm tắt
A SAR ADC is a type of analog-to-digital converter that uses a binary search algorithm to convert an analog input into a digital code. It employs a comparator and a digital-to-analog converter (DAC) to successively approximate the input voltage, achieving high resolution and speed with low power consumption. SAR ADCs are widely used in applications requiring high precision and moderate sampling rates, such as industrial process control, medical instrumentation, and scientific analysis.
Key features of the AD7984BCPZ include 18-bit resolution with no missing codes, a true differential analog input range of ±VREF with VREF between 5.0 V, and an INL of ±2.25 LSB maximum. It offers a dynamic range of 99.7 dB typical and a signal-to-noise ratio (SNR) of 99 dB typical. The device features an SPI-compatible serial interface that supports daisy-chaining multiple ADCs on a single 3-wire bus and provides an optional busy indicator. The reference voltage is applied externally and can be set independent of the supply voltage.
The AD7984BCPZ is pin-for-pin compatible with the 18-bit AD7982, allowing easy upgrades or substitutions in existing designs. It can interface with any 1.8 V to 5 V digital logic family, providing flexibility in mixed-voltage systems. The device operates over a temperature range of -40°C to +125°C, making it suitable for harsh industrial environments.
Typical applications include high-speed data acquisition, medical imaging, spectroscopy, and vibration analysis. Its low power dissipation and high accuracy make it particularly well-suited for battery-powered portable instruments and remote sensing nodes.
When designing with the AD7984BCPZ, ensure a clean, low-impedance reference voltage source and adequate decoupling on the VDD and REF pins. The SPI interface should be kept short to minimize noise, and the analog input should be driven by a low-impedance source to maintain accuracy.
Bộ thay thế dễ dàng lắp đặt cho AD7984BCPZ — 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 AD7984BCPZ (cùng hình factor và footprint) — khác nhau ở Input Type, Operating Temperature, Resolution, Data Interface, Sampling Rate.
AD7984-1BCPZ-RL7
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD7984-5BCPZ-R2
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD7982BCPZ
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →AD7980BCPZ-RL7
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →AD7984BCPZ Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 18 bits |
| Tỷ lệ lấy mẫu | 1.33 MSPS |
| Number of Inputs | 1 |
| Input Type | Differential |
| Data Interface | SPI |
| Architecture | SAR |
| Reference Type | External |
| Voltage - Supply, Analog | 2.5 V |
| Voltage - Supply, Digital | 1.8 V to 5 V |
| INL (Max) | ±2.25 LSB |
| Dynamic Range | 99.7 dB typical |
| SNR (Typical) | 99 dB |
| Power Dissipation | 10.5 mW at 1.33 MSPS |
| Nhiệt độ hoạt động | -40°C to +125°C |
| Hộp | 10-LFCSP-WD (3x3 mm) |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
Cấu hình chân AD7984BCPZ
| Chân 1 | IN+ — Positive analog input |
| Chân 2 | IN- — Negative analog input |
| Chân 3 | GND — Ground |
| Chân 4 | VDD — Power supply (2.5V) |
| Chân 5 | REF — Reference voltage input |
| Chân 6 | SDI — Serial data input (for daisy-chain) |
| Chân 7 | SDO — Serial data output |
| Chân 8 | SCK — Serial clock input |
| Chân 9 | CNV — Convert input (start conversion) |
| Chân 10 | VIO — Digital interface supply |
Ứng dụng tiêu biểu
AD7984BCPZ phù hợp cho 6 Áp dụngs: High-Speed Data Acquisition, Medical Imaging, Spectroscopy, Vibration Analysis, Portable Instrumentation, Industrial Process Control.
High-Speed Data Acquisition
The AD7984BCPZ's 1.33 MSPS sampling rate and 18-bit resolution make it ideal for high-speed data acquisition systems. Its low power dissipation of 10.5 mW allows dense multi-channel designs without excessive heat. The SPI interface simplifies connection to microcontrollers and DSPs, enabling rapid data transfer. The true differential input rejects common-mode noise, ensuring accurate capture of small signals in noisy industrial environments.
Được đề xuất
Medical Imaging
In medical imaging systems such as X-ray and ultrasound, the AD7984BCPZ provides the high resolution and dynamic range needed to capture fine anatomical details. Its 99.7 dB dynamic range ensures weak echoes are distinguished from noise. The low power consumption is beneficial for portable devices. The small LFCSP package allows compact probe designs. The SPI interface enables easy integration with imaging processors.
Được đề xuất
Spectroscopy
The AD7984BCPZ is well-suited for spectroscopy applications where precise measurement of light intensity is required. Its 18-bit resolution and low INL (±2.25 LSB) ensure accurate representation of spectral peaks. The high SNR (99 dB) minimizes noise, allowing detection of weak spectral lines. The external reference allows calibration to the specific sensor output. The SPI interface supports high-speed data streaming to analysis software.
Được đề xuất
Vibration Analysis
For vibration monitoring in industrial machinery, the AD7984BCPZ captures high-frequency vibration signals with 18-bit precision. Its 1.33 MSPS sampling rate allows analysis of frequencies up to 600 kHz, covering most mechanical vibrations. The low power dissipation enables deployment in wireless sensor nodes. The differential input reduces electromagnetic interference from motors. The SPI interface allows daisy-chaining multiple ADCs for multi-axis monitoring.
Được đề xuất
Portable Instrumentation
The AD7984BCPZ's low power consumption (10.5 mW) and small package make it ideal for portable instruments like handheld multimeters and data loggers. Its 18-bit resolution ensures accurate measurements in field applications. The wide operating temperature range (-40°C to +125°C) allows use in harsh environments. The SPI interface simplifies connection to low-power microcontrollers. The external reference enables calibration for different measurement ranges.
Được đề xuất
Industrial Process Control
In industrial process control, the AD7984BCPZ provides accurate conversion of sensor signals for monitoring and control loops. Its 18-bit resolution and low INL ensure precise measurement of temperature, pressure, and flow. The true differential input rejects common-mode noise from long cable runs. The SPI interface supports daisy-chaining multiple ADCs for multi-channel systems. The wide temperature range and low power make it suitable for field-mounted transmitters.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho AD7984BCPZ — 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 | AD7984-1BCPZ-RL7 | AD7984-5BCPZ-R2 | AD7982BCPZ | AD7980BCPZ-RL7 |
|---|---|---|---|---|---|
| Package | 10-LFCSP-WD (3x3 mm) | 10-LFCSP-WD (3x3 mm) | 10-LFCSP-WD (3x3 mm) | 10-LFCSP-WD (3x3 mm) | 10-LFCSP-WD (3x3 mm) |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 18 bits | 18 bits | 16 bits | 18 bits | 16 bits |
| Sampling Rate | 1.33 MSPS | 1.33 MSPS | 1.33 MSPS | 1 MSPS | 1 MSPS |
| Power Dissipation | 10.5 mW | 10.5 mW | 10.5 mW | 10.5 mW | 7 mW |
| INL (Max) | ±2.25 LSB | ±2.25 LSB | ±2.25 LSB | ±2.25 LSB | ±1.5 LSB |
| Dynamic Range | 99.7 dB | 99.7 dB | 99.7 dB | 99.7 dB | 93.5 dB |
| SNR (Typical) | 99 dB | 99 dB | 99 dB | 99 dB | 91.5 dB |
Bảo phân biệt quan trọng
- Higher sampling rate than AD7982 (vsAD7982BCPZ)
- Lower power than AD7980 at same speed (vsAD7980BCPZ-RL7)
- Pin-compatible with AD7982 (vsAD7982BCPZ)
Ghi chú thiết kế
The AD7984BCPZ requires a clean 2.5V analog supply (VDD) and a separate digital interface supply (VIO) that can range from 1.8V to 5V. Use low-ESR ceramic capacitors (e.g., 10uF and 0.1uF) placed close to the VDD and VIO pins to decouple high-frequency noise. The reference voltage (REF) should be driven by a low-impedance source, such as a precision reference buffer, to ensure accurate conversions.
For optimal performance, place the AD7984BCPZ on a solid ground plane and minimize trace lengths for the analog input and reference. Use a star-ground topology to separate analog and digital grounds, connecting them at a single point. Keep the SPI lines (SCK, SDO, SDI, CNV) short and avoid routing them near high-speed digital signals to prevent crosstalk. Consider adding a series resistor (e.g., 33 ohm) on the SCK line to reduce ringing.
A common pitfall is driving the analog input with a high-impedance source, which can cause sampling errors due to the ADC's input capacitance. Use a low-impedance driver, such as an op-amp buffer, to ensure the input settles within the acquisition time. Also, ensure the reference voltage is stable and noise-free; any noise on REF directly affects the conversion accuracy. Finally, avoid exceeding the absolute maximum ratings on VDD and VIO to prevent damage.
Thông tin tuân thủ
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.