16-Bit, 250 kSPS PulSAR
®
ADC in MSOP
Data Sheet
AD7694
Rev. B Document Feedback
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FEATURES
16-bit resolution with no missing codes
Throughput: 250 kSPS at 5 V
INL: ±4 LSB max
S/(N + D): 92 dB at 20 kHz
THD: –106 dB at 20 kHz
Pseudo-differential analog input range:
0 V to V
REF
with V
REF
up to VDD
No pipeline delay
Single-supply operation: 2.7 V or 5 V
Proprietary serial interface
SPI®-/QSPI™-/MICROWIRE™-/DSP-compatible
1
Supply Current: 540 μA at 2.7 V/100 kSPS,
800 μA at 5 V/100 kSPS
Standby current: 1 nA
8-lead MSOP package
Improved second source to LTC1864 and LTC1864L
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−. e 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.
APPLICATION DIAGRAM
AD7694
REF
GND
VDD
IN+
IN–
SCK
SDO
CNV
3-WIRE SPI
INTERFACE
1V TO VDD 2.5V TO 5V
0 TO V
REF
05003-001
Figure 1.
Table 1. MSOP, LFCSP (QFN)/SOT-23, 16-Bit PulSAR ADC
Type 100 kSPS 250 kSPS 500 kSPS
True Differential AD7684 AD7687 AD7688
Pseudo AD7683 AD7685 AD7686
Differential/Unipolar AD7694
Unipolar AD7680
1
Protected by U.S. Patent 6,703,961.