Analog Devices AD7986 Product Info

• 18-bit resolution with no missing codes
• Throughput: 2 MSPS (TURBO = high), 1.5 MSPS (TURBO = low)
• Low power dissipation
• 15 mW at 2 MSPS, with external reference
• 26 mW at 2 MSPS with internal reference
• INL: ±1 LSB typical, ±2.5 LSB maximum
• SNR
• 95.5 dB, with on-chip reference
• 97.0 dB, with external reference
• 4.096 V internal reference: typical drift of 10 ppm/°C
• True differential analog input voltage range: ±V_REF
• 0 V to V_REF with V_REF up to 5.0 V
• Allows use of any input range
• See data sheet for additional features

The AD7986 is an 18-bit, 2 MSPS successive approximation, analog-to-digital converter (ADC). It contains a low power, high speed, 18-bit sampling ADC, an internal conversion clock, an internal reference (and buffer), error correction circuits, and a versatile serial interface port. On the rising edge of CNV, the AD7986 samples the voltage difference between the IN+ and IN− pins. The voltages on these pins usually swing in opposite phases between 0 V and V_REF. It features a very high sampling rate turbo mode (TURBO = high) and a reduced power normal mode (TURBO = low) for low power applications where the power is scaled with the throughput.

In normal mode (TURBO = low), the SPI-compatible serial interface also features the ability, using the SDI input, to daisychain several ADCs on a single 3-wire bus and provide an optional busy indicator. It is compatible with 1.8 V, 2.5 V, and 2.7 V using the separate VIO supply.

The AD7986 is available in a 20-lead LFCSP with operation specified from −40°C to +85°C.

Applications

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