16-Bit, 100 kSPS PulSAR
Differential ADC in MSOP

AD7684


Rev. 0
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FEATURES
16-bit resolution with no missing codes
Throughput: 100 kSPS
INL: ±1 LSB typ, ±3 LSB max
True differential analog input range: ±VREF
0 V to VREF with VREF 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
V
REF
0
V
REF

Figure 1.

Table 1. MSOP, QFN (LFCSP)/SOT-23, 16-Bit PulSAR ADCs
Type 100 kSPS 250 kSPS 500 kSPS
True Differential AD7684 AD7687 AD7688
Pseudo
Differential/Unipolar
AD7683 AD7685
AD7694
AD7686
Unipolar AD7680

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 package, with an
operating temperature specified from −40°C to +85°C.