Datasheet AD7691 (Analog Devices)

18-Bit, 1.5 LSB INL, 250 kSPS PulSAR Differential ADC in MSOP/LFCSP Data Sheet AD7691 FEATURES APPLICATION DIAGRAM 18-bit resolution with no missing codes +0.5V TO VDD +2.5V TO +5V Throughput: 250 kSPS INL: ±0.75 LSB typical, ±1.5 LSB maximum (±6 ppm of FSR) Dynamic range: 102 dB typical at 250 kSPS REF VDD VIO +1.8V TO VDD Oversampled dynamic range: 125 dB at1 kSPS IN+ SDI SCK 3- OR 4-WIRE Noise-free code resolution: 20 bits at 1 kSPS ±10V, ±5V, ... INTERFACE IN– SDO (SPI, DAISY CHAIN, CS) Effective resolution: 22.7 bits at 1 kSPS GND CNV ADA4941 SINAD: 101.5 dB typical at 1 kHz
001
THD: −125 dB typical at 1 kHz AD7691
06146-
True differential analog input range: ±V
Figure 2.
REF 0 V to VREF with VREF up to VDD on both inputs No pipeline delay Table 1. MSOP, LFCSP/SOT-23 14-/16-/18-Bit PulSAR® ADC Single-supply 2.3 V to 5 V operation with 100 250 400 kSPS to ≥1000 ADC 1.8 V/2.5 V/3 V/5 V logic interface Type kSPS kSPS 500 kSPS kSPS Driver Proprietary serial interface
18-Bit True AD7691 AD7690 AD7982 ADA4941-1
SPI/QSPI/MICROWIRE™/DSP compatible
Differential AD7984 ADA4841-2
Ability to daisy-chain multiple ADCs
16-Bit True AD7684 AD7687 AD7688 ADA4941-1 Differential AD7693 ADA4841-2
Optional busy indicator feature
16-Bit AD7680 AD7685 AD7686 AD7980 ADA4841-1
Power dissipation
Pseudo AD7683 AD7694
1.35 mW at 2.5 V/100 kSPS, 4 mW at 5 V/100 kSPS
Differential
1.4 µW at 2.5 V/100 SPS
14-Bit AD7940 AD7942 AD7946 ADA4841-1 Pseudo
Standby current: 1 nA
Differential
10-lead packages: MSOP (MSOP-8 size) and 3 mm × 3 mm LFCSP (SOT-23 size) Pin-for-pin compatible with the18-bit AD7690 a nd GENERAL DESCRIPTION 16-bit AD7693, AD7688, and AD7687
The AD76911 is an 18-bit, charge redistribution, successive
APPLICATIONS
approximation, analog-to-digital converter (ADC) that operates
Battery-powered equipment
from a single power supply, VDD, between 2.3 V and 5 V. It
Data acquisitions
contains a low power, high speed, 18-bit sampling ADC with no
Seismic data acquisition systems
missing codes, an internal conversion clock, and a versatile
Instrumentation
serial interface port. On the CNV rising edge, it samples the
Medical instruments
voltage difference between the IN+ and IN− pins. The voltages
1.5
on these pins swing in opposite phases between 0 V and REF.
POSITIVE INL = 0.43LSB NEGATIVE INL = –0.62LSB
The reference voltage, REF, is applied externally and can be set
1.0
up to the supply voltage. The part’s power scales linearly with throughput.
0.5 ) B
The SPI-compatible serial interface also features the ability,
LS 0 L (
using the SDI input, to daisy-chain several ADCs on a single
IN
3-wire bus and provides an optional busy indicator. It is compatible
–0.5
with 1.8 V, 2.5 V, 3 V, or 5 V logic, using the separate VIO supply.
–1.0
The AD7691 is housed in a 10-lead MSOP or a 10-lead LFCSP with operation specified from −40°C to +85°C.
–1.5 0 65536 131072 196608 262144
025 1 Protected by U.S. Patent 6,703,961.
CODE
06146- Figure 1. Integral Nonlinearity vs. Code, 5 V
Rev. E Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 ©2006–2015 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com
Document Outline FEATURES APPLICATIONS APPLICATION DIAGRAM GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS Thermal Resistance ESD CAUTION PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION CIRCUIT INFORMATION CONVERTER OPERATION Transfer Functions TYPICAL CONNECTION DIAGRAM ANALOG INPUTS DRIVER AMPLIFIER CHOICE SINGLE-TO-DIFFERENTIAL DRIVER VOLTAGE REFERENCE INPUT POWER SUPPLY SUPPLYING THE ADC FROM THE REFERENCE DIGITAL INTERFACE CS\ MODE, 3-WIRE WITHOUT BUSY INDICATOR CS\ MODE, 3-WIRE WITH BUSY INDICATOR CS\ MODE, 4-WIRE WITHOUT BUSY INDICATOR CS\ MODE, 4-WIRE WITH BUSY INDICATOR CHAIN MODE WITHOUT BUSY INDICATOR CHAIN MODE WITH BUSY INDICATOR APPLICATION HINTS LAYOUT EVALUATING THE AD7691 PERFORMANCE OUTLINE DIMENSIONS ORDERING GUIDE