AD7682BCPZRL7

The AD7682/AD7689 are 4-channel/8-channel, 16-bit, charge redistribution successive approximation register (SAR) analog-to-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 serial port interface (SPI) fo 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 lead frame chip scale package (LFCSP) and 20-lead wafer level chip scale package (WLCSP) with operation specified from -40°C to +85°C. The AD7689 includes an extended temperature range model with specifications guaranteed to a maximum temperature (TMAX) of +125°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

Key features

• 16-bit resolution with no missing codes
• 4-channel (AD7682)/8-channel (AD7689) 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