Overview
The AD7731BRU, manufactured by Analog Devices Inc., is a 24-bit Sigma-Delta Analog-to-Digital Converter (ADC) designed for high-precision data acquisition. This device is particularly suited for process control applications, offering a complete analog front-end with a proprietary programmable gain stage. This allows it to handle a wide range of input signal levels directly from transducers. The AD7731BRU operates from a single +5 V supply and features a sigma-delta architecture with an analog modulator and a low-pass programmable digital filter, enabling adjustable filter cutoff, output rate, and settling time.
Key Specifications
| Parameter | Value | Conditions/Comments |
|---|---|---|
| Resolution | 24 bits | - |
| Peak-to-Peak Resolution at 800 Hz Output Rate | 16 bits | - |
| Programmable Output Rates | Up to 6.4 kHz | fCLK IN = 4.9152 MHz |
| Input Ranges (Unipolar) | 0 to +20 mV, +40 mV, +80 mV, +160 mV, +320 mV, +640 mV, +1.28 V | - |
| Input Ranges (Bipolar) | ±20 mV, ±40 mV, ±80 mV, ±160 mV, ±320 mV, ±640 mV, ±1.28 V | - |
| Supply Voltage | +5 V | - |
| Package Type | 24-lead TSSOP, 24-lead SOIC, 24-lead plastic DIP | - |
| Operating Temperature Range | −40°C to +85°C | - |
| Offset Drift | < 5 nV/°C | - |
| Gain Drift | < 2 ppm/°C | - |
Key Features
- 24-bit Sigma-Delta ADC with high precision and low noise.
- Programmable gain front end to accommodate various input signal ranges.
- Three buffered differential programmable gain analog inputs, configurable as five pseudo-differential inputs.
- Differential reference input.
- Adjustable filter cutoff, output rate, and settling time through a low-pass programmable digital filter.
- Serial interface compatible with microcontrollers and digital signal processors, configurable for three-wire operation.
- Self-calibration and system calibration options.
- Fast channel switching with 1 ms settling time.
Applications
- Process control systems.
- Industrial automation.
- High-precision data acquisition systems.
- Transducer interface applications.
- Medical devices requiring high accuracy and low noise.
Q & A
- What is the resolution of the AD7731BRU?
The AD7731BRU has a 24-bit resolution, with a peak-to-peak resolution of 16 bits at an 800 Hz output rate.
- What are the input ranges supported by the AD7731BRU?
The device supports seven unipolar and seven bipolar input ranges, from 0 to +1.28 V and ±1.28 V respectively.
- What is the operating supply voltage of the AD7731BRU?
The device operates from a single +5 V supply.
- What types of packages are available for the AD7731BRU?
The AD7731BRU is available in 24-lead TSSOP, 24-lead SOIC, and 24-lead plastic DIP packages.
- What is the operating temperature range of the AD7731BRU?
The device operates over a temperature range of −40°C to +85°C.
- Does the AD7731BRU support self-calibration?
Yes, the AD7731BRU supports both self-calibration and system calibration options.
- How fast can the AD7731BRU switch between channels?
The device can switch between channels with a settling time of 1 ms.
- Is the AD7731BRU compatible with microcontrollers and digital signal processors?
Yes, the serial interface of the AD7731BRU is compatible with microcontrollers and digital signal processors and can be configured for three-wire operation.
- What is the gain drift and offset drift of the AD7731BRU?
The gain drift is less than 2 ppm/°C, and the offset drift is less than 5 nV/°C.
- What are some typical applications of the AD7731BRU?
Typical applications include process control systems, industrial automation, high-precision data acquisition systems, transducer interface applications, and medical devices requiring high accuracy and low noise.
