Datasheet LTC2378-18 (Analog Devices)

LTC2378-18 18-Bit, 1Msps, Low Power SAR ADC with 102dB SNR
FeaTures DescripTion
n
1Msps Throughput Rate
The LTC®2378-18 is a low noise, low power, high speed n
±1.75LSB INL (Max)
18-bit successive approximation register (SAR) ADC. Op- n
Guaranteed 18-Bit No Missing Codes
erating from a 2.5V supply, the LTC2378-18 has a ±VREF n
Low Power: 13.5mW at 1Msps, 13.5µW at 1ksps
fully differential input range with VREF ranging from 2.5V n
102dB SNR (typ) at fIN = 2kHz
to 5.1V. The LTC2378-18 consumes only 13.5mW and n –
124dB THD (typ) at fIN = 2kHz
achieves ±1.75LSB INL maximum, no missing codes at n
Digital Gain Compression (DGC)
18 bits with 102dB SNR. n Guaranteed Operation to 125°C The LTC2378-18 has a high speed SPI-compatible serial n 2.5V Supply interface that supports 1.8V, 2.5V, 3.3V and 5V logic while n Fully Differential Input Range ±VREF also featuring a daisy-chain mode. The fast 1Msps through- n VREF Input Range from 2.5V to 5.1V put with no cycle latency makes the LTC2378-18 ideally n No Pipeline Delay, No Cycle Latency suited for a wide variety of high speed applications. An n 1.8V to 5V I/O Voltages internal oscillator sets the conversion time, easing external n SPI-Compatible Serial I/O with Daisy-Chain Mode timing considerations. The LTC2378-18 automatical y pow- n Internal Conversion Clock ers down between conversions, leading to reduced power n 16-Lead MSOP and 4mm × 3mm DFN Packages dissipation that scales with the sampling rate.
applicaTions
The LTC2378-18 features a unique digital gain compres- sion (DGC) function, which eliminates the driver amplifier’s n Medical Imaging negative supply while preserving the full resolution of the n High Speed Data Acquisition ADC. When enabled, the ADC performs a digital scaling n Portable or Compact Instrumentation function that maps zero-scale code from 0V to 0.1 • VREF n Industrial Process Control and full-scale code from VREF to 0.9 • VREF. For a typical n Low Power Battery-Operated Instrumentation reference voltage of 5V, the full-scale input range is now n ATE 0.5V to 4.5V, which provides adequate headroom for L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the powering the driving amplifier from a single 5.5V supply. property of their respective owners.
Typical applicaTion 32k Point FFT fS = 1Msps, fIN = 2kHz
2.5V 1.8V TO 5V 0 SNR = 102.3dB 10µF 0.1µF –20 THD = –124dB SINAD = 102.2dB –40 SFDR = 126dB V VDD OVDD CHAIN REF 20Ω 6800pF –60 + RDL/SDI IN+ 0V SDO –80 V 3300pF LTC2378-18 SCK REF BUSY –100 – IN– CNV SAMPLE CLOCK 0V 20Ω 6800pF REF GND REF/DGC VREF AMPLITUDE (dBFS) –120 2.5V TO 5.1V 237818 TA01a –140 47µF –160 (X5R, 0805 SIZE) –180 0 100 200 300 400 500 FREQUENCY (kHz) 237818 TA01b 237818fa For more information www.linear.com/LTC2378-18 1 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Converter Characteristics Dynamic Accuracy Reference Input Digital Inputs and Digital Outputs Power Requirements ADC Timing Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Timing Diagram Applications Information Board Layout Package Description Revision History Typical Application Related Parts