AD7890BR-4 - 8-Channel 12-Bit DAS | Analog Devices
MPN: AD7890BR-4 ✓ Hoạt độngAD7890BR-4 Tóm tắt
A data acquisition system (DAS) is a complete signal chain that samples multiple analog signals, converts them to digital, and outputs the data to a processor. It typically includes a multiplexer, an ADC, a track/hold amplifier, and a reference. The AD7890BR-4 integrates these functions into a single IC, reducing board space and design complexity. In the hierarchy of signal chain components, a DAS sits above a standalone ADC, as it includes the multiplexer and reference, but below a full system-on-chip that might include a microcontroller. This integration is particularly valuable in multi-channel monitoring applications where space is constrained.
Key features of the AD7890BR-4 include its 8 single-ended analog input channels, 12-bit resolution, and a serial interface that simplifies connection to microcontrollers and DSPs. The device offers a choice of input ranges: ±10 V (AD7890-10), 0 V to 4.096 V (AD7890-4), and 0 V to 2.5 V (AD7890-2). The on-chip track/hold amplifier ensures accurate sampling of fast-changing signals, while the on-chip reference eliminates the need for an external reference, saving cost and board area. The device operates over a temperature range of -40°C to +85°C, making it suitable for industrial environments.
Technically, the AD7890BR-4 uses a successive approximation register (SAR) architecture, which provides a good balance of speed and resolution. The 5.9 µs conversion time corresponds to a maximum sample rate of approximately 117 kSPS when all channels are scanned sequentially. The serial interface is SPI-compatible, with a clock input and data output, allowing easy integration with most microcontrollers. The device also features a busy output that indicates when a conversion is in progress, simplifying synchronization.
Typical applications include industrial process control, where multiple sensors need to be monitored; data acquisition systems for test and measurement; and battery-powered instrumentation, where the low power consumption and single-supply operation are advantageous. The AD7890BR-4 is also suitable for medical monitoring equipment and automotive test systems.
When designing with the AD7890BR-4, ensure that the analog input signals are within the specified range and that adequate decoupling is provided on the power supply pins. The serial interface should be isolated if the system is subject to high noise, and the reference output should be buffered if driving external loads.
Bộ thay thế dễ dàng lắp đặt cho AD7890BR-4 — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
AD7890BRZ-4
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
AD7890BR-4 Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bits |
| Number of Channels | 8 single-ended |
| Conversion Time | 5.9 µs |
| Sample Rate | 117 kSPS |
| Analog Input Range | 0 V to 4.096 V |
| Điện áp cung cấp | 5 V (single) |
| Giao diện | Serial (SPI-compatible) |
| Hộp | 24-SOIC (narrow) |
| Khoảng nhiệt độ hoạt động | -40°C to +85°C |
| On-Chip Track/Hold | Yes |
| On-Chip Reference | Yes |
| Technology | LC2MOS |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
| Số lượng chân | 24 |
Cấu hình chân AD7890BR-4
| Chân 1 | VIN0 — Analog input channel 0 |
| Chân 2 | VIN1 — Analog input channel 1 |
| Chân 3 | VIN2 — Analog input channel 2 |
| Chân 4 | VIN3 — Analog input channel 3 |
| Chân 5 | VIN4 — Analog input channel 4 |
| Chân 6 | VIN5 — Analog input channel 5 |
| Chân 7 | VIN6 — Analog input channel 6 |
| Chân 8 | VIN7 — Analog input channel 7 |
| Chân 9 | AGND — Analog ground |
| Chân 10 | VREF — Reference voltage output/input |
| Chân 11 | DGND — Digital ground |
| Chân 12 | SCLK — Serial clock input |
| Chân 13 | SDATA — Serial data output |
| Chân 14 | CS — Chip select (active low) |
| Chân 15 | BUSY — Busy output (high during conversion) |
| Chân 16 | VDD — Power supply (5V) |
| Chân 17 | NC — No connect |
| Chân 18 | NC — No connect |
| Chân 19 | NC — No connect |
| Chân 20 | NC — No connect |
| Chân 21 | NC — No connect |
| Chân 22 | NC — No connect |
| Chân 23 | NC — No connect |
| Chân 24 | NC — No connect |
Ứng dụng tiêu biểu
AD7890BR-4 phù hợp cho 6 Áp dụngs: Industrial Process Control, Data Acquisition Systems, Battery-Powered Instrumentation, Medical Monitoring Equipment, Automotive Test Systems, Test and Measurement Equipment.
Industrial Process Control
The AD7890BR-4 is ideal for industrial process control systems that monitor multiple sensors such as temperature, pressure, and flow. Its 8-channel multiplexer allows direct connection of up to 8 analog sensors, while the 12-bit resolution provides sufficient accuracy for control loops. The 5.9 µs conversion time enables fast sampling of dynamic process variables, and the serial interface simplifies isolation and communication with PLCs or microcontrollers. The device operates from a single 5 V supply, which is common in industrial control panels, and its -40°C to +85°C temperature range ensures reliable operation in harsh environments. The on-chip track/hold amplifier ensures accurate sampling of rapidly changing signals, and the on-chip reference eliminates the need for external reference components, reducing board space and cost.
Được đề xuất
Data Acquisition Systems
In general-purpose data acquisition systems, the AD7890BR-4 provides a compact, integrated solution for digitizing multiple analog signals. Its 8 single-ended channels can be used to monitor various inputs, and the serial interface allows easy connection to a wide range of microcontrollers and DSPs. The 12-bit resolution is suitable for many measurement applications, and the 117 kSPS sample rate supports moderate-speed data logging. The device's low power consumption and single-supply operation make it suitable for portable and battery-powered data loggers. The independently accessible multiplexer allows the insertion of antialiasing filters or signal conditioning circuits between the mux and the ADC, providing design flexibility. The on-chip reference ensures stable conversions over temperature, which is critical for accurate measurements.
Được đề xuất
Battery-Powered Instrumentation
The AD7890BR-4 is well-suited for battery-powered instrumentation due to its low power consumption and single 5 V supply operation. It can be powered directly from a 5 V battery or a regulated supply, and its low quiescent current extends battery life. The 8-channel multiplexer allows monitoring of multiple battery cells or system parameters, and the 12-bit resolution provides adequate precision for voltage and current monitoring. The serial interface minimizes the number of I/O lines required, reducing microcontroller pin usage. The device's small SOIC-24 package is ideal for space-constrained portable devices. The on-chip track/hold and reference reduce external component count, further saving space and power. The operating temperature range of -40°C to +85°C ensures reliable operation in various environmental conditions.
Được đề xuất
Medical Monitoring Equipment
In medical monitoring equipment, the AD7890BR-4 can be used to digitize signals from multiple physiological sensors, such as ECG, temperature, and pressure. Its 8-channel multiplexer allows simultaneous monitoring of several parameters, and the 12-bit resolution is sufficient for many diagnostic applications. The device's low power consumption is critical for portable and wearable medical devices. The serial interface simplifies data transfer to a processing unit, and the on-chip reference ensures accurate conversions. The -40°C to +85°C operating range covers the typical medical device temperature requirements. The small SOIC-24 package is suitable for compact designs. The independently accessible multiplexer allows the insertion of signal conditioning circuits, such as filters and amplifiers, between the mux and the ADC, which is essential for medical signal processing.
Được đề xuất
Automotive Test Systems
The AD7890BR-4 is suitable for automotive test systems that require monitoring of multiple analog signals, such as battery voltage, temperature, and pressure. Its 8-channel multiplexer allows connection of multiple sensors, and the 12-bit resolution provides adequate accuracy for test and measurement. The device operates from a single 5 V supply, which is common in automotive electronics, and its -40°C to +85°C temperature range is suitable for under-hood and in-cabin environments. The serial interface simplifies integration with automotive microcontrollers and CAN transceivers. The on-chip track/hold ensures accurate sampling of dynamic signals, and the on-chip reference reduces external component count. The small SOIC-24 package is suitable for space-constrained automotive modules.
Được đề xuất
Test and Measurement Equipment
In test and measurement equipment, the AD7890BR-4 provides a versatile front-end for digitizing multiple analog signals. Its 8-channel multiplexer allows monitoring of various test points, and the 12-bit resolution is suitable for many benchtop instruments. The 5.9 µs conversion time enables fast data acquisition, and the serial interface allows easy connection to a host processor. The device's low power consumption is beneficial for portable test equipment. The on-chip reference ensures stable measurements over temperature, and the independently accessible multiplexer allows the insertion of programmable gain amplifiers or filters. The SOIC-24 package is easy to integrate into PCB designs. The device's wide operating temperature range makes it suitable for both laboratory and field use.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho AD7890BR-4 — 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 | AD7890BRZ-4 | AD7890ANZ-4 | AD7890AN-2 | AD7890ANZ-10 |
|---|---|---|---|---|---|
| Package | 24-SOIC | 24-SOIC | 24-PDIP | 24-PDIP | 24-PDIP |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Input Range | 0 V to 4.096 V | 0 V to 4.096 V | 0 V to 4.096 V | 0 V to 2.5 V | ±10 V |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Conversion Time | 5.9 µs | 5.9 µs | 5.9 µs | 5.9 µs | 5.9 µs |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V | 5 V |
| Interface | Serial | Serial | Serial | Serial | Serial |
| Operating Temperature | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C |
Bảo phân biệt quan trọng
- Integrated 8-channel multiplexer (vsAD7890ANZ-10)
- Small SOIC-24 package (vsAD7890ANZ-4)
- On-chip reference and track/hold (vsMAX1308)
Ghi chú thiết kế
The AD7890BR-4 operates from a single 5 V supply. It is recommended to decouple the VDD pin with a 10 µF tantalum capacitor in parallel with a 0.1 µF ceramic capacitor placed as close to the pin as possible. The analog and digital grounds should be connected at a single point to minimize noise. If the supply is noisy, an LC filter can be added.
For optimal performance, place the AD7890BR-4 on a PCB with a solid ground plane. Keep analog input traces short and shielded from digital signals. Use separate analog and digital ground planes if possible, and connect them at the device. Ensure that the reference output is bypassed with a 0.1 µF capacitor to ground.
A common mistake is exceeding the absolute maximum input voltage on the analog inputs. The AD7890BR-4 accepts 0 V to 4.096 V; applying voltages outside this range can damage the device. Also, ensure that the serial interface timing meets the specifications in the datasheet to avoid communication errors. The BUSY signal should be monitored to ensure conversions are complete before reading data.
Thông tin tuân thủ
RoHS compliant per Analog Devices product page. Lead-free version is AD7890BRZ-4.
