AD7685BCPZ - 16-Bit 250kSPS PulSAR ADC | Analog Devices
MPN： AD7685BCPZ ✓ 啟用中AD7685BCPZ 概覽
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 output. It employs a charge redistribution capacitor array to perform the conversion, offering a balance of speed, resolution, and power consumption. SAR ADCs are widely used in applications requiring high accuracy and moderate sampling rates, such as industrial process control, medical instrumentation, and portable battery-powered devices.
Key features of the AD7685BCPZ include 16-bit resolution with no missing codes, a 250 kSPS sampling rate, and a low power consumption of typically 3.5 mW at 5 V supply. The device also features a pseudo-differential input, an SPI-compatible serial interface, and a power-down mode for energy savings. The LFCSP package provides excellent thermal performance and a small footprint, enabling high-density PCB layouts.
The AD7685 uses a charge redistribution architecture with an internal track-and-hold circuit, ensuring accurate sampling of the input signal. The device includes a precision reference input that can be driven by an external reference, allowing flexibility in system design. The SPI interface supports daisy-chaining of multiple ADCs, simplifying multi-channel data acquisition systems.
Typical applications include battery-powered instrumentation, data acquisition systems, industrial process control, and medical devices. The AD7685's low power and high accuracy make it suitable for portable and remote sensing applications where power efficiency is critical.
When designing with the AD7685BCPZ, ensure a clean analog supply and a stable reference voltage to achieve optimal performance. Proper PCB layout with adequate decoupling and grounding is essential to minimize noise and maximize SNR.
直接替換替代品，適用於 AD7685BCPZ — 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： AD7685BCPZ （相同外形與佔位） — 差異在於 Sampling Rate, Input Type, Resolution, Package, Supply Voltage.
AD7685BCPZ-R2
✅ 直接替換📋 參考替代品（不在目錄中）
AD7685BCPZRL7
✅ 直接替換📋 參考替代品（不在目錄中）
AD7690BCPZRL7
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →AD7980BCPZ-RL7
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →AD7980BCPZ-RL7
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →AD7685BCPZ 最大額定值與電氣特性
| 解析度 | 16 bits |
| 取樣率 | 250 kSPS |
| Input Type | Pseudo-differential |
| 供應電壓 | 2.3 V to 5.5 V |
| Power Consumption | 3.5 mW at 5 V |
| 介面 | SPI |
| 封裝 | 10-LFCSP-WD (3x3 mm) |
| 工作溫度 | -40C to +125C |
| No Missing Codes | Yes |
| 參考電壓 | External, 0.5V to VDD |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant |
AD7685BCPZ 腳位配置
| 腳位 1 | VDD — Power supply, 2.3V to 5.5V |
| 腳位 2 | GND — Ground |
| 腳位 3 | REF — Reference input, external |
| 腳位 4 | IN+ — Positive analog input |
| 腳位 5 | IN- — Negative analog input |
| 腳位 6 | SDO — Serial data output |
| 腳位 7 | SCK — Serial clock input |
| 腳位 8 | CS — Chip select, active low |
| 腳位 9 | PD — Power down, active high |
| 腳位 10 | EP — Exposed pad, connect to GND |
典型應用
AD7685BCPZ 適用於 6 應用s: Battery-Powered Instrumentation, Data Acquisition Systems, Industrial Process Control, Medical Instrumentation, Portable Test Equipment, Sensor Signal Conditioning.
Battery-Powered Instrumentation
The AD7685BCPZ's low power consumption (3.5 mW at 5 V) and wide supply range (2.3 V to 5.5 V) make it ideal for portable instruments. Its 16-bit resolution ensures accurate measurements, while the small LFCSP package saves board space. The SPI interface simplifies connection to low-power microcontrollers, and power-down modes extend battery life in duty-cycled applications.
推薦
Data Acquisition Systems
The AD7685BCPZ provides 16-bit resolution at 250 kSPS, making it suitable for multi-channel data acquisition systems. Its pseudo-differential input rejects common-mode noise, and the SPI interface supports daisy-chaining for multiple channels. The device's low power and small footprint enable high-density designs in industrial and laboratory equipment.
推薦
Industrial Process Control
In industrial process control, the AD7685BCPZ offers the accuracy and speed needed for monitoring sensors and actuators. Its 16-bit resolution ensures precise control, while the wide supply range accommodates various industrial power rails. The device's robust operating temperature range (-40C to +125C) suits harsh environments, and the SPI interface integrates easily with industrial microcontrollers.
推薦
Medical Instrumentation
The AD7685BCPZ is well-suited for medical devices such as patient monitors and diagnostic equipment. Its low power consumption is critical for battery-operated devices, and the 16-bit resolution provides the accuracy required for vital sign measurements. The compact LFCSP package allows miniaturization, and the SPI interface enables easy integration with medical-grade microcontrollers.
推薦
Portable Test Equipment
For portable test equipment like handheld multimeters and data loggers, the AD7685BCPZ offers a balance of performance and power efficiency. Its 250 kSPS sampling rate is sufficient for many test applications, and the low power consumption extends battery life. The small package and SPI interface make it easy to design into compact, battery-powered devices.
推薦
Sensor Signal Conditioning
The AD7685BCPZ is ideal for conditioning signals from sensors such as temperature, pressure, and strain gauges. Its 16-bit resolution captures fine sensor variations, and the pseudo-differential input helps reject noise. The device's low power and small size are advantageous in distributed sensor networks, and the SPI interface allows easy connection to sensor hub microcontrollers.
推薦
推薦產品摘要
工程參考資料，適用於 AD7685BCPZ — 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 | AD7685BCPZ-R2 | AD7685BCPZRL7 | AD7690BCPZRL7 | 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 | 16 bits | 16 bits | 16 bits | 16 bits | 16 bits |
| Sampling Rate | 250 kSPS | 250 kSPS | 250 kSPS | 400 kSPS | 1 MSPS |
| Supply Voltage | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V |
| Interface | SPI | SPI | SPI | SPI | SPI |
| Input Type | Pseudo-differential | Pseudo-differential | Pseudo-differential | Pseudo-differential | Pseudo-differential |
主要差異化特點
- Low power consumption of 3.5 mW at 5V (對比AD7980BCPZ)
- 250 kSPS sampling rate (對比AD7690BCPZRL7)
- Small 10-lead LFCSP package (對比AD7980BCPZ)
設計說明
The AD7685BCPZ operates from 2.3V to 5.5V. Use a low-noise LDO to supply VDD and a precision reference for REF. Decouple VDD with a 10uF and 0.1uF capacitor close to the pin. The reference input should be bypassed with a 10uF capacitor to ensure stable operation.
For optimal performance, place the AD7685BCPZ close to the signal source and use a solid ground plane. Keep analog and digital grounds separate and connect them at a single point. Route the SPI lines away from analog inputs to minimize crosstalk.
Ensure the input signal is within the specified common-mode range. The pseudo-differential input requires IN- to be connected to a reference voltage, typically GND. Avoid floating the PD pin; tie it to GND if not used. Also, ensure the SPI clock does not exceed the maximum specified frequency.
合規資訊
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.