Datasheet AD7946 (Analog Devices)

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14-Bit, 500 kSPS, PulSAR ADC in MSOP and LFCSP Data Sheet AD7946 FEATURES TYPICAL APPLICATION CIRCUIT 14-bit resolution with no missing codes 0.5V TO 5V 5V Throughput: 500 kSPS INL: ±0.4 LSB typical, ±1 LSB maximum (±0.0061% of FSR) SINAD: 85 dB at 20 kHz REF VDD VIO 1.8V TO VDD 0V TO REF THD: −100 dB at 20 kHz SDI IN+ Pseudo differential analog input range AD7946 SCK 3- OR 4-WIRE INTERFACE IN– SDO (SPI, DAISY CHAIN, CS) 0 V to REF with REF up to VDD GND CNV
001
No pipeline delay
04656-
Single-supply 5 V operation with 1.8 V/2.5 V/3 V/5 V logic
Figure 1.
interface Proprietary serial interface GENERAL DESCRIPTION SPI-/QSPI™-/ MICROWIRE™-/DSP-compatible
The AD79461 is a 14-bit, charge redistribution, successive
Daisy-chain multiple ADCs and BUSY indicator
approximation, analog-to-digital converter (ADC) that operates
Power dissipation
from a single 5 V power supply, VDD. It contains a low power,
3.3 mW at 5 V/100 kSPS
high speed, 14-bit sampling ADC with no missing codes, an
3.3 µW at 5 V/100 SPS
internal conversion clock, and a versatile serial interface port.
Standby current: 1 nA
The part also contains a low noise, wide bandwidth, short
10-lead MSOP (MSOP-8 size) and
aperture delay track-and-hold circuit. On the CNV rising edge,
3 mm × 3 mm LFCSP (SOT-23 size)
it samples an analog input IN+ between 0 V to REF with respect
Pin-for-pin compatible with the 16-bit AD7686
to a ground sense IN−. The reference voltage, REF, is applied
APPLICATIONS
external y and can be set up to the supply voltage.
Battery-powered equipment
Its power scales linearly with throughput.
Data acquisition
The SPI-compatible serial interface also features the ability,
Instrumentation
using the SDI input, to daisy-chain several ADCs on a single,
Medical instruments
3-wire bus, or it provides an optional BUSY indicator. It is
Process control
compatible with 1.8 V, 2.5 V, 3 V, or 5 V logic, using the separate supply VIO. The AD7946 is housed in a 10-lead MSOP or a 10-lead LFCSP with operation specified from −40°C to +85°C. 1 Protected by U.S. Patent 6,703,961.
Table 1. MSOP, LFCSP 14-/16-/18-Bit PulSAR® ADC Type 100 kSPS 250 kSPS 400 kSPS to 500 kSPS ≥1000 kSPS ADC Driver
14-Bit AD7940 AD79421 AD79461 16-Bit AD7680 AD76851 AD76861 AD79801 ADA4941 AD7683 AD76871 AD76881 AD79831 ADA4841 AD7684 AD7694 AD76931 18-Bit AD76911 AD76901 AD79821 ADA4941 AD79841 ADA4841 1 Pin-for-pin compatible.
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Document Outline Features Applications Typical Application Circuit General Description Table of Contents Revision History Specifications Timing Specifications Absolute Maximum Ratings ESD Caution Pin Configurations and Function Descriptions Typical Performance Characteristics Terminology Theory of Operation Circuit Information Converter Operation Transfer Functions Typical Connection Diagram Analog Input Driver Amplifier Choice Voltage Reference Input Power Supply Supplying the ADC from the Reference Single-Supply Application Digital Interface CS/ MODE 3-Wire, No BUSY Indicator CS/ Mode 3-Wire with BUSY Indicator CS/ Mode 4-Wire, No BUSY Indicator CS/ Mode 4-Wire with BUSY Indicator Chain Mode, No BUSY Indicator Chain Mode with BUSY Indicator Application Guidelines Layout Evaluating the Performance of the AD7946 Outline Dimensions Ordering Guide