Analog Devices Inc. AD7685 16-Bit PulSAR ADCs

Analog Devices Inc. AD7685 16-bit PulSAR® Analog-to-Digital Converters (ADC) are designed as charge redistribution, successive-approximation ADCs operating from a single VDD power supply between 2.3V to 5.5V. AD7685 features a low-power, high speed, 16-bit sampling ADC with no missing codes, an internal conversion clock, and a versatile serial interface port. These devices also include a low noise, wide bandwidth, short aperture delay, track-and-hold circuit. AD7685 ADCs are compatible with 1.8V, 2.5V, 3V, or 5V logic, using the separate VIO supply. Using the SPI-compatible serial interface, designers can daisy-chain several ADCs on a single 3-wire bus or provide an optional BUSY indicator. Available in a 10-lead MSOP or a 10-lead (QFN) LFCSP package with operation specified from −40°C to +85°C, AD7685 16-bit PulSAR ADCs are ideal for battery-powered equipment, mobile communications, data acquisition, personal digital assistants (PDAs), medical instruments, instrumentation, and process controls.


  • 16-bit resolution with no missing codes
  • 250kSPS Throughput
  • ±0.6 LSB typical, ±2 LSB maximum (±0.003% of FSR) INL
  • 93.5dB at 20kHz SINAD
  • −110dB at 20kHz THD
  • Pseudo-differential analog input range
  • 0V to VREF with VREF up to VDD
  • No pipeline delay
  • Single-supply operation 2.3V to 5.5V with 1.8V to 5V logic interface
  • Proprietary serial interface: SPI-/QSPI™-/MICROWIRE™-/DSP-compatible
  • Daisy-chain multiple ADCs, BUSY indicator
  • Power dissipation
    • 1.4μW at 2.5V/100 SPS
    • 1.35mW at 2.5V/100 kSPS, 4mW at 5V/100 kSPS
  • Standby current: 1nA
  • 10-lead package: MSOP (MSOP-8 size) and 3mm × 3mm LFCSP (SOT-23 size)
  • Pin-for-pin-compatible with 10-lead MSOP/PulSAR® ADCs


  • Battery-powered equipment
  • Medical instruments
  • Mobile communications
  • Personal digital assistants(PDAs)
  • Data acquisition
  • Instrumentation
  • Process controls

Typical Application Circuit

Application Circuit Diagram - Analog Devices Inc. AD7685 16-Bit PulSAR ADCs
Published: 2014-07-31 | Updated: 2022-03-11