16-Bit, 100 kSPS PulSAR,
Differential ADC in MSOP
AD7684
Rev. A
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FEATURES
16-bit resolution with no missing codes
Throughput: 100 kSPS
INL: ±1 LSB typical, ±3 LSB maximum
True differential analog input range: ±V
REF
0 V to V
REF
with V
REF
up to VDD on both inputs
Single-supply operation: 2.7 V to 5.5 V
Serial interface SPI®-/QSPI-™/MICROWIRE-™/DSP-compatible
Power dissipation
4 mW @ 5 V
1.5 mW @ 2.7 V
150 μW @ 2.7 V/10 kSPS
Standby current: 1 nA
8-lead MSOP package
APPLICATIONS
Battery-powered equipment
Data acquisition
Instrumentation
Medical instruments
Process control
APPLICATION DIAGRAM
AD7684
REF
GND
VDD
+IN
–IN
DCLOCK
D
OUT
CS
3-WIRE SPI
INTERFACE
0.5V TO VDD 2.7V TO 5.5V
04302-001
0
REF
0
REF
Figure 1.
Table 1. MSOP, QFN (LFCSP)/SOT-23
14-/16-/18-Bit PulSAR ADC
Type
100
kSPS
250
kSPS
400 kSPS
to
500 kSPS
≥ 1000
kSPS
ADC
Driver
18-Bit True AD7691 AD7690 AD7982 ADA4941
Differential AD7984 ADA4841
16-Bit True AD7684 AD7687 AD7688 ADA4941
Differential AD7693 ADA4841
16-Bit Pseudo AD7680 AD7685 AD7686 AD7980 ADA4841
Differential AD7683 AD7694
14-Bit Pseudo
Differential
AD7940 AD7942 AD7946 ADA4841
GENERAL DESCRIPTION
The AD7684 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 5.5 V. It contains a low power, high speed, 16-bit sampling
ADC with no missing codes, 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
CS
falling edge, it samples the voltage difference
between +IN and –IN pins. The reference voltage, REF, is
applied externally and can be set up to the supply voltage. Its
power scales linearly with throughput.
The AD7684 is housed in an 8-lead MSOP, with an operating
temperature specified from −40°C to +85°C.
