The AD7949 is an 8-channel, 14-bit, charge redistribution successive approximation register (SAR) analog-to-digital converter (ADC) that operates from a single power supply, VDD.
The AD7949 contains all components for use in a multichannel, low power data acquisition system, including a true 14-bit SAR ADC with no missing codes; an 8-channel, low crosstalk multiplexer that is useful for configuring the inputs as single-ended (with or without ground sense), differential, or bipolar; an internal low drift reference (selectable 2.5 V or 4.096 V) and buffer; a temperature sensor; a selectable one-pole filter; and a sequencer that is useful when channels are continuously scanned in order.
The AD7949 uses a simple SPI interface for writing to the configuration register and receiving conversion results. The SPI interface uses a separate supply, VIO, which is set to the host logic level. Power dissipation scales with throughput.
The AD7949 is housed in a tiny 20-lead LFCSP with operation specified from −40°C to +85°C.
**Applications**
Multichannel system monitoring
Battery-powered equipment
Medical instruments: ECG/EKG
Mobile communications: GPS
Personal digital assistants
Power line monitoring
Data acquisition
Seismic data acquisition systems
Instrumentation
Process control
### Features and Benefits
14-bit resolution with no missing codes
8-channel multiplexer with choice of inputs
Unipolar single-ended
Differential (GND sense)
Pseudobipolar
Throughput: 250 kSPS
INL/DNL: ±0.5/±0.25 LSB typical
SINAD: 85 dB @ 20 kHz
THD: −100 dB @ 20 kHz
Analog input range: 0 V to VREF with VREF up to VDD
See data sheet for additional features
**AD7949-EP supports defense and aerospace applications (AQEC standard)**