
Analog Devices
GENERAL DESCRIPTION
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.
FEATURES
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 LSB typical
SINAD: 85 dB @ 20 kHz
THD: 100 dB @ 20 kHz
Analog input range: 0 V to VREF with VREF up to VDD
Multiple reference types
Internal selectable 2.5 V or 4.096 V
External buffered (up to 4.096 V)
External (up to VDD)
Internal temperature sensor
Channel sequencer, selectable 1-pole filter, busy indicator
No pipeline delay, SAR architecture
Single-supply 2.7 V to 5.5 V operation with
1.8 V to 5 V logic interface
Serial interface compatible with SPI, MICROWIRE,
QSPI, and DSP
Power dissipation
2.9 mW @ 2.5 V/200 kSPS
10.8 mW @ 5 V/250 kSPS
Standby current: 50 nA
20-lead 4 mm × 4 mm LFCSP package
APPLICATIONS
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