●Product Details
●The AD7682/AD7689 are 4-channel/8-channel, 16-bit, charge redistribution successive approximation register (SAR) analogto-digital converters (ADCs) that operate from a single power supply, VDD.
●The AD7682/AD7689 contain all components for use in a multichannel, low power data acquisition system, including a true 16-bit SAR ADC with no missing codes; a 4-channel (AD7682) or 8-channel (AD7689) 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 AD7682/AD7689 use 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 AD7682/AD7689 are housed in a tiny 20-lead LFCSP and 20-lead WLCSP with operation specified from −40°C to +85°C.
●Applications
● Multichannel system monitoring
● Battery-powered equipment
● Medical instruments: ECG/EKG
● Mobile communications: GPS
● Power line monitoring
● Data acquisition
● Seismic data acquisition systems
● Instrumentation
● Process control
●### Features and Benefits
● 16-bit resolution with no missing codes
● 4-channel multiplexer with choice of inputs
● Unipolar single-ended
● Differential (GND sense)
● Pseudobipolar
● Throughput: 250 kSPS
● INL: ±0.4 LSB typical, ±1.5 LSB maximum (±23 ppm or FSR)
● Dynamic range: 93.8 dB
● SINAD: 92.5 dB at 20 kHz
● THD: −100 dB at 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 (TEMP)
● Channel sequencer, selectable 1-pole filter, busy indicator
● No pipeline delay, SAR architecture
● Single-supply 2.3 V to 5.5 V operation with 1.8 V to 5.5 V logic interface
● Serial interface compatible with SPI, MICROWIRE, QSPI, and DSP
● Power dissipation
● 3.5 mW at 2.5 V/200 kSPS
● 12.5 mW at 5 V/250 kSPS
● Standby current: 50 nA
● Low cost grade available
● 20-lead 4 mm × 4 mm LFCSP package
● 20-lead 2.4 mm × 2.4 mm WLCSP package