Catalog
14-Bit, 8-Channel, 250kSPS PulSAR ADC
Key Features
• 14-bit resolution with no missing codes
• 8-channel multiplexer with choice of inputsUnipolar single-endedDifferential (GND sense)Pseudobipolar
• Multiple reference typesInternal selectable 2.5 V or 4.096 VExternal buffered (up to 4.096 V)External (up to VDD)
• See datasheet for additional features
Description
AI
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.APPLICATIONSMultichannel system monitoringBattery-powered equipmentMedical instruments: ECG/EKGMobile communications: GPSPersonal digital assistantsPower line monitoringData acquisitionSeismic data acquisition systemsInstrumentationProcess control
