AD7690BRMZ

The AD7690 is an 18-bit, successive approximation, analog-to-digital converter (ADC) that operates from a single power supply, VDD. It contains a low power, high speed, 18-bit sampling ADC with no missing codes, an internal conversion clock, and a versatile serial interface port. On the CNV rising edge, it samples the voltage difference between the IN+ and IN- pins. The voltages on these pins swing in opposite phase between 0V and REF. The reference voltage, REF, is applied externally and can be set up to the supply voltage. The power of the AD7690 scales linearly with the throughput. The SPI-compatible serial interface also features the ability, using the SDI input, to daisy-chain several ADCs on a single, 3-wire bus and provides an optional busy indicator. It is compatible with 1.8V, 2.5V, 3V, or 5V logic, using the separate VIO supply. The AD7690 is housed in a 10-lead MSOP or a 10-lead LFCSP with operation specified from -40°C to +85°C

Applications

• Battery-powered equipment
• Data acquisition
• Seismic data acquisition systems
• DVMs
• Instrumentation
• Medical instruments

Key features

• 18-bit resolution with no missing codes
• Throughput: 400kSPS
• INL: ±0.75 LSB typical, ±1.5 LSB maximum (6 ppm of FSR)
• Dynamic range: 102 dB at 400 kSPS
• Oversampled dynamic range: 125 dB at 1 kSPS
• Noise-free code resolution: 20 bits at 1 kSPS
• Effective resolution: 22.2 bits at 1 kSPS
• SINAD: 101.5 dB at 1 kHz
• THD: -125 dB at 1 kHz
• True differential analog input range: VREF 0V to VREF with VREF up to VDD on both inputs
• No pipeline delay
• Single-supply 5 V operation with 1.8V/2.5V/3V/5V logic interface
• Proprietary serial interface SPI/QSPI/MICROWIRE*/DSP compatible
• Daisy-chain multiple ADCs and busy indicator
• Power dissipation 4.25μW at 100SPS, 4.25mW at 100kSPS
• Standby current: 1 nA
• 10-lead package: MSOP (MSOP-8 size) and 3mm×3mm LFCSP (SOT-23 size)
• Pin-for-pin compatible with LFCSP/MSOP PulSAR ADCs