LTC2378-20 20-Bit, 1Msps, Low Power SAR ADC with 0.5ppm INL FeaTuresDescripTion n 1Msps Throughput Rate The LTC®2378-20 is a low noise, low power, high speed n ±0.5ppm INL (Typ) 20-bit successive approximation register (SAR) ADC. n Guaranteed 20-Bit No Missing Codes Operating from a 2.5V supply, the LTC2378-20 has a n Low Power: 21mW at 1Msps, 21µW at 1ksps ±VREF fully differential input range with VREF ranging from n 104dB SNR (Typ) at fIN = 2kHz 2.5V to 5.1V. The LTC2378-20 consumes only 21mW and n – 125dB THD (Typ) at fIN = 2kHz achieves ±2ppm INL maximum, no missing codes at 20 n Digital Gain Compression (DGC) bits with 104dB SNR. n Guaranteed Operation to 85°C The LTC2378-20 has a high speed SPI-compatible serial n 2.5V Supply interface that supports 1.8V, 2.5V, 3.3V and 5V logic n Fully Differential Input Range ±VREF while also featuring a daisy-chain mode. The fast 1Msps n VREF Input Range from 2.5V to 5.1V throughput with no cycle latency makes the LTC2378-20 n No Pipeline Delay, No Cycle Latency ideally suited for a wide variety of high speed applications. n 1.8V to 5V I/O Voltages An internal oscillator sets the conversion time, easing exter- n SPI-Compatible Serial I/O with Daisy-Chain Mode nal timing considerations. The LTC2378-20 automatically n Internal Conversion Clock powers down between conversions, leading to reduced n 16-Lead MSOP and 4mm × 3mm DFN Packages power dissipation that scales with the sampling rate. applicaTions The LTC2378-20 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. Patents Pending. Protected by U.S. Patents, including 7705765, 7961132, 8319673. Typical applicaTionIntegral Nonlinearity vs Output Code 2.5V 1.8V TO 5V 2.0 1.5 10µF 0.1µF 1.0 V VDD OVDD CHAIN REF 10Ω 6800pF 0.5 + RDL/SDI IN+ 0V SDO 0 V 3300pF LTC2378-20 SCK REF – BUSY IN– –0.5 CNV SAMPLE CLOCK INL ERROR (ppm) 0V 10Ω 6800pF REF GND REF/DGC VREF –1.0 2.5V TO 5.1V 237820 TA01a –1.5 47µF (X7R, 1210 SIZE) –2.0 –524288 –262144 0 262144 524288 OUTPUT CODE 237820 TA01b 237820fb For more information www.linear.com/LTC2378-20 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration 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