16-Bit, 2 LSB INL, 3 MSPS PulSAR
®
ADC
AD7621
Rev. 0
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FEATURES
Throughput
3 MSPS (wideband warp and warp mode)
2 MSPS (normal mode)
1.25 MSPS (impulse mode)
2.048 V internal reference
Differential input range: ±V
REF
(V
REF
up to 2.5 V)
INL: ±2 LSB maximum, ±1 LSB typical
16-bit resolution with no missing codes
SINAD: 89 dB typical @ 100 kHz
THD: −101 dB typical @ 100 kHz
No pipeline delay (SAR architecture)
Parallel (16- or 8-bit bus) and serial 5 V/3.3 V/2.5 V interface
SPI®-/QSPI™-/MICROWIRE™-/DSP-compatible
2.5 V single-supply operation
Power dissipation: 65 mW typical @ 3 MSPS
48-lead LQFP and 48-lead LFCSP_VQ packages
Speed upgrade of the AD7677
APPLICATIONS
Medical instruments
High speed data acquisition
Digital signal processing
Communications
Instrumentation
Spectrum analysis
ATE
FUNCTIONAL BLOCK DIAGRAM
04565-001
16
CONTROL LOGIC AND
CALIBRATION CIRCUITRY
CLOCK
AD7621
DGNDDVDD
AVDD
AGND
REF REFGND
IN+
IN–
PD
RESET
CNVST
PDBUF
REFBUFIN
WARP
IMPULSE
PDREF
REF
TEMP
D[15:0]
BUSY
RD
CS
OB/2C
OGND
OVDD
BYTESWAP
SER/PAR
REF AMP
SERIAL
PORT
PARALLEL
INTERFACE
SWITCHED
CAP DAC
Figure 1.
Table 1. PulSAR Selection
Type/kSPS 100 to 250 500 to 570
800 to
1000
>1000
Pseudo
Differential
AD7651
AD7660/61
AD7650/52
AD7664/66
AD7653
AD7667
True Bipolar AD7663 AD7665 AD7671
True
Differential
AD7675 AD7676 AD7677 AD7621
18-Bit AD7678 AD7679 AD7674 AD7641
Multichannel/
Simultaneous
AD7654 AD7655
GENERAL DESCRIPTION
The AD7621 is a 16-bit, 3 MSPS, charge redistribution SAR,
fully differential analog-to-digital converter (ADC) that
operates from a single 2.5 V power supply. It contains a high
speed 16-bit sampling ADC, an internal conversion clock, an
internal reference (and buffer), error correction circuits, and
both serial and parallel system interface ports. It features two
very high sampling rate modes (wideband warp and warp), a
fast mode (normal) for asynchronous rate applications, and a
reduced power mode (impulse) for low power applications
where the power is scaled with the throughput. Operation is
specified from −40°C to +85°C.
PRODUCT HIGHLIGHTS
1. Fast Throughput.
The AD7621 is a 3 MSPS, charge redistribution,
16-bit SAR ADC.
2. Superior Linearity.
The AD7621 has no missing 16-bit code.
3. Internal Reference.
The AD7621 has a 2.048 V internal reference with a
typical drift of ±7 ppm/°C.
4. Single-Supply Operation.
The AD7621 operates from a 2.5 V single supply and
typically dissipates 65 mW. In impulse mod
e, its power
e throughput.
5.
ace
arrangement compatible with 2.5 V, 3.3 V, or 5 V logic.
dissipation decreases with th
Serial or Parallel Interface.
Versatile parallel (16- or 8-bit bus) or 2-wire serial interf
