Δ-Σ ADC
Δ-Σ ADC

Product Model
DADS1247
The DADS1247 is a precision 24-bit analog-to-digital converter (ADC) that includes numerous integrated features to reduce system cost and component count for sensor measurement applications. This chip features a low-noise programmable gain amplifier (PGA), a single-cycle digital filter, a high-precision Delta-Sigma (ΔΣ) A/D converter, and an internal oscillator. The DADS1247 also provides a built-in, low-drift reference voltage and two matched programmable excitation current sources (IDACs). The DADS1247's input analog multiplexer supports four differential inputs. Furthermore, this multiplexer integrates sensor failure detection, thermocouple voltage biasing, system monitoring, and general-purpose digital I/O.
The programmable gain amplifier (PGA) offers selectable gain up to 128x. These features provide a complete front-end solution for temperature sensor measurement applications, including thermocouples, thermistors, and resistance temperature detectors (RTDs), as well as other small-signal measurements including resistance bridge sensors. The digital filter enables single-cycle setup to support fast channel cycling when using the input multiplexer and provides data rates up to 2kSPS. For data rates of 20 SPS or lower, the filter will suppress harmonic interference at 50 Hz and 60 Hz power frequency.
Features
- Programmable data rate: up to 2kSPS.
- Single-cycle setup for all data rates.
- Achieve 50Hz and 60Hz harmonic suppression at 20SPS.
- Analog multiplexer with 4 independently selectable inputs.
- Low-noise programmable gain amplifier: 48nVRMS when PGA=128.
- Two matched programmable excitation current sources.
- Integrated low-drift 2.048V reference voltage: 10ppm/°C.
- Sensor failure detection.
- 4 general purpose input /output interfaces.
- Built-in temperature sensor.
- Power supply and reference voltage monitoring.
- Self-calibration and system calibration.
- SPI interface compatible.
- Analog power supply: unipolar (2.7V) to 5.25V) and bipolar (±2.5V) operating voltage.
- Digital power supply: 2.7V to 5.25V.
Applications
- Temperature sensor measurement:
- Resistance temperature detectors (RTDs), thermocouples and thermistors.
- Pressure measurement.
- Flow meter.
- Factory automation and process control.
Specifications
Product Model | Resolution (bits) | Sampling Rate | Channels | ENOB | Power Dissipation (mw) | Temperature Range (°C) | Package Type | Datasheet |
|---|---|---|---|---|---|---|---|---|
DADS1247 | 24 | 2ksps | 4 | 19.5 | 1.27 | -40°C ~ 85°C | SSOP-20 |
