Overview
The AD7794BRU, manufactured by Analog Devices Inc., is a high-precision, low-power, 24-bit Sigma-Delta analog-to-digital converter (ADC). This device is designed for a wide range of high-precision measurement applications, including temperature measurement, pressure measurement, weigh scales, and industrial process control. The AD7794BRU features an integrated low-noise instrumentation amplifier, a precision band gap reference, and programmable gain settings, making it suitable for interfacing with small amplitude signals directly. The device operates with a power supply range of 2.7V to 5.25V and is housed in a 24-lead Thin Shrink Small Outline Package (TSSOP).
Key Specifications
| Category | Data |
|---|---|
| Manufacturer | Analog Devices Inc. |
| Package / Case | 24-TSSOP (0.173", 4.40mm Width) |
| Number of Bits | 24 |
| Architecture | Sigma-Delta |
| Configuration | MUX-ADC |
| Mounting Type | Surface Mount |
| Data Interface | SPI, DSP |
| Number of Inputs | 6 (Differential) |
| Operating Temperature | -40°C ~ 105°C (B grade), -40°C ~ 125°C (C grade) |
| Voltage - Supply, Analog/Digital | 2.7V ~ 5.25V |
| Sampling Rate (Per Second) | 4.17 Hz to 470 Hz |
| Reference Type | External, Internal |
Key Features
- Low noise, 24-bit Sigma-Delta ADC with up to 23 effective bits RMS noise.
- Integrated low-noise instrumentation amplifier and precision band gap reference.
- Programmable gain settings (1 to 128) and programmable excitation current sources.
- On-chip bias voltage generator and burnout currents for sensor protection.
- Low-side power switch to power down bridge sensors between conversions, minimizing power consumption.
- Support for internal or external clock and simultaneous 50 Hz/60 Hz rejection.
- 3-wire serial interface compatible with SPI, QSPI, MICROWIRE, and DSP.
- Low power consumption: 400 μA typical, 1 μA maximum in power-down mode.
Applications
- Temperature measurement
- Pressure measurement
- Weigh scales
- Strain gage transducers
- Gas analysis
- Industrial process control
- Instrumentation
- Blood analysis
- Smart transmitters
- Liquid/gas chromatography
- 6-digit DVM (Digital Voltmeter)
Q & A
- What is the resolution of the AD7794BRU ADC?
The AD7794BRU is a 24-bit Sigma-Delta ADC, providing up to 23 effective bits of resolution.
- What is the operating temperature range of the AD7794BRU?
The operating temperature range is -40°C to 105°C for B-grade parts and -40°C to 125°C for C-grade parts.
- What are the power supply requirements for the AD7794BRU?
The device operates with a power supply range of 2.7V to 5.25V for both analog and digital supplies.
- What types of interfaces does the AD7794BRU support?
The AD7794BRU supports SPI, QSPI, MICROWIRE, and DSP interfaces.
- What are the key features of the integrated instrumentation amplifier in the AD7794BRU?
The integrated instrumentation amplifier is low-noise and allows for direct interfacing with small amplitude signals. It also includes programmable gain settings and a precision band gap reference.
- How does the AD7794BRU manage power consumption?
The device includes a low-side power switch to power down bridge sensors between conversions, minimizing system power consumption. It consumes 400 μA typical and 1 μA maximum in power-down mode.
- What are some common applications of the AD7794BRU?
Common applications include temperature measurement, pressure measurement, weigh scales, strain gage transducers, gas analysis, and industrial process control.
- Does the AD7794BRU support external references?
Yes, the AD7794BRU can accept up to two external differential references in addition to its internal reference.
- What is the sampling rate range of the AD7794BRU?
The sampling rate can vary from 4.17 Hz to 470 Hz.
- Is the AD7794BRU RoHS compliant?
No, the AD7794BRU contains lead and is not RoHS compliant.
