GENERAL DESCRIPTION
The AD7641 is a 18-bit, 2 MSPS, charge redistribution SAR, fully differential analog-to-digital converter that operates from a single 2.5 V power supply. The part contains a high-speed 18-
bit sampling ADC, an internal conversion clock, an internal reference buffer, error correction circuits, and both serial and parallel system interface ports. It features a very high sampling rate mode (Warp) and a fast mode (Normal) for asynchronous conversion rate applications. The AD7641 is hardware factory calibrated and comprehensively tested to ensure ac parameters
such as signal-to-noise ratio (SNR) and total harmonic distortion (THD) in addition to the more traditional dc parameters of gain, offset and linearity. Operation is specified from −40°C to +85°C.

FEATURES
Throughput
   2 MSPS (wideband warp and warp mode)
   1.5 MSPS (normal mode)
INL: ±2 LSB typical, ±3 LSB max; ±8 ppm of full scale
18-bit resolution with no missing codes
Dynamic range: 95.5 dB
SNR: 93.5 dB typical @ 20 kHz (VREF= 2.5 V)
THD: −112 dB typical @ 20 kHz (VREF= 2.5 V)
2.048 V internal reference: typ drift 10 ppm/°C; TEMP output
Differential input range: ±VREF(VREFup to 2.5 V)
No pipeline delay (SAR architecture)
Parallel (18-, 16-, or 8-bit bus) and serial 5 V/3.3 V/2.5 V interface
SPI®/QSPI™/MICROWIRE™/DSP compatible
Single 2.5 V supply operation
Power dissipation
   75 mW typical @ 2 MSPS with internal REF
   2 μW in power-down mode
Pb-free, 48-lead LQFP and 48-lead LFCSP_VQ
Speed upgrade of the AD7674, AD7678, AD7679

APPLICATIONS
Medical instruments
High speed data acquisition/high dynamic data acquisition
Digital signal processing
Spectrum analysis
Instrumentation
Communications
ATE