16-Bit, 250 kSPS PulSAR® ADC in MSOP
AD7694
APPLICATION DIAGRAM
FEATURES
1V TO VDD
2.5V TO 5V
16-bit resolution with no missing codes
Throughput: 250 kSPS @ 5 V
INL: 4 LSB max
REF
VDD
S/(N + D): 92 dB @ 20 kHz
0 TO V
REF
IN+
SCK
SDO
CNV
THD: –106 dB @ 20 kHz
AD7694
3-WIRE SPI
INTERFACE
IN–
Pseudo-differential analog input range:
0 V to VREF with VREF up to VDD
No pipeline delay
GND
Single-supply operation: 2.7 V or 5 V
Serial interface SPI®/QSPI™/MICROWIRE™/DSP-compatible
Supply Current: 540 μA @ 2.7 V/100 kSPS,
800 μA @ 5 V/100 kSPS
Standby current: 1 nA
8-lead MSOP package
Figure 1.
Table 1. MSOP, LFCSP (QFN)/SOT-23, 16-Bit PulSAR ADC
Type
100 kSPS
AD7684
AD7683
250 kSPS
AD7687
AD7685
AD7694
500 kSPS
AD7688
AD7686
True Differential
Pseudo
Differential/Unipolar
Unipolar
Improved second source to LTC1864 and LTC1864L
AD7680
APPLICATIONS
Battery-powered equipment
Data acquisition
Instrumentation
Medical instruments
Process control
GENERAL DESCRIPTION
The AD7694 is a 16-bit, charge redistribution, successive
approximation, PulSAR analog-to-digital converter (ADC) that
operates from a single power supply, VDD, between 2.7 V to
5.25 V. It contains a low power, high speed, 16-bit sampling
ADC with no missing codes (B grade), an internal conversion
clock, and a serial, SPI-compatible interface port. The part also
contains a low noise, wide bandwidth, short aperture delay
track-and-hold circuit. On the CNV rising edge, it samples an
analog input, IN+, between 0 V to REF with respect to a ground
sense, IN−. The reference voltage, REF, is applied externally and
can be set up to the supply voltage.
Its power scales linearly with throughput.
The AD7694 is housed in an 8-lead MSOP package with an
operating temperature specified from −40°C to +85°C.
Rev. A
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