Overview
The AD7794BRU-REEL, produced by Analog Devices Inc., is a 24-bit, low noise, low power Sigma-Delta Analog-to-Digital Converter (ADC). This device is designed for high precision measurement applications and features six differential analog inputs. It is part of the AD7794/AD7795 family, which includes complete analog front ends with on-chip instrumentation amplifiers, precision references, and programmable current sources. The AD7794 is housed in a 24-lead Thin Shrink Small Outline Package (TSSOP) and is suitable for a wide range of applications requiring high accuracy and low power consumption.
Key Specifications
| Parameter | Value | Unit | Test Conditions/Comments |
|---|---|---|---|
| Resolution | 24 Bits | - | - |
| Output Update Rate | 4.17 Hz to 470 Hz | - | Settling time = 2/output update rate |
| Integral Nonlinearity | ±15 ppm of FSR max | - | - |
| Offset Error | ±1 μV typ | - | - |
| Offset Error Drift vs. Temperature | ±10 nV/°C typ | - | - |
| Full-Scale Error | ±10 μV typ | - | - |
| Gain Drift vs. Temperature | ±1 ppm/°C typ (Gain = 1 to 16, external reference) | - | - |
| Power Supply | 2.7 V to 5.25 V | - | - |
| Temperature Range | B grade: –40°C to +105°C, C grade: –40°C to +125°C | - | - |
| Package | 24-lead TSSOP | - | - |
| Interface | 3-wire serial interface (SPI®, QSPI™, MICROWIRE™, and DSP compatible) | - | - |
Key Features
- Low noise, 24-bit Sigma-Delta ADC with six differential inputs
- On-chip low noise instrumentation amplifier for direct interface with small amplitude signals
- Precision, low noise, low drift internal band gap reference and support for up to two external differential references
- Programmable excitation current sources and burnout currents
- Bias voltage generator to set the common-mode voltage of a channel to AVDD/2
- Low-side power switch to power down bridge sensors between conversions, minimizing power consumption
- Internal clock oscillator with the option to use an external clock
- Simultaneous 50 Hz/60 Hz rejection and reference detect
- Independent interface power supply
- Schmitt trigger on SCLK for robust clocking
Applications
- Temperature measurement
- Pressure measurement
- Weigh scales
- Strain gage transducers
- Gas analysis
- Industrial process control and instrumentation
- Blood analysis
- Smart transmitters
- Liquid/gas chromatography
- 6-digit DVM (Digital Voltmeter)
Q & A
- What is the resolution of the AD7794BRU-REEL?
The AD7794BRU-REEL has a resolution of 24 bits.
- What is the output update rate of the AD7794BRU-REEL?
The output update rate ranges from 4.17 Hz to 470 Hz.
- What is the temperature range for the AD7794BRU-REEL?
The B grade parts are specified for a temperature range of –40°C to +105°C, while the C grade parts are specified for –40°C to +125°C.
- What type of package does the AD7794BRU-REEL come in?
The AD7794BRU-REEL is housed in a 24-lead Thin Shrink Small Outline Package (TSSOP).
- Does the AD7794BRU-REEL support external references?
- What are some of the key features of the on-chip instrumentation amplifier?
The on-chip instrumentation amplifier is low noise and allows for direct interface with small amplitude signals.
- How does the AD7794BRU-REEL minimize power consumption?
The device includes a low-side power switch that can power down bridge sensors between conversions, minimizing the system’s power consumption.
- What types of interfaces does the AD7794BRU-REEL support?
The AD7794BRU-REEL supports 3-wire serial interfaces including SPI®, QSPI™, MICROWIRE™, and DSP compatible interfaces.
- What are some common applications for the AD7794BRU-REEL?
- What is the power supply range for the AD7794BRU-REEL?
