LTC2389-18 18-Bit, 2.5Msps SAR ADC with Pin-Configurable Analog Input Range and 99.8dB SNR FeaTuresDescripTion n 2.5Msps Throughput Rate The LTC®2389-18 is a low noise, high speed 18-bit n ±3LSB INL (Max) successive approximation register (SAR) ADC. Operating n Guaranteed 18-Bit, No Missing Codes from a single 5V supply, the LTC2389-18 supports pin- n Pin-Configurable Analog Input Range: configurable fully differential (±4.096V), pseudo-differ- ±4.096V Fully Differential ential unipolar (0V to 4.096V), and pseudo-differential 0V to 4.096V Pseudo-Differential Unipolar bipolar (±2.048V) analog input ranges, allowing it to ±2.048V Pseudo-Differential Bipolar interface with multiple signal chain formats without re- n 99.8dB (Fully Differential)/ 95.2dB (Pseudo quiring additional level translation or signal conditioning. Differential) SNR (Typ) at fIN = 2kHz The LTC2389-18 achieves ±3LSB INL (maximum), no n –116dB (Fully Differential)/–112dB (Pseudo missing codes at 18-bits, and 99.8dB (fully differential)/ Differential) THD (Typ) at fIN = 2kHz 95.2dB (pseudo differential) SNR (typical). n Guaranteed Operation to 125°C The LTC2389-18 includes a precision internal 4.096V n Single 5V Supply reference, with a guaranteed 0.5% initial accuracy and a n Internal 20ppm/°C (Max) Reference ±20ppm/°C (maximum) temperature coefficient, as well n Internal Reference Buffer as an internal reference buffer. Fast 2.5Msps throughput n 162.5mW Power Dissipation at 2.5Msps with no cycle latency in the parallel interface modes n No Pipeline Delay, No Cycle Latency makes the LTC2389-18 ideally suited for a wide variety n 1.8V to 5V I/O Voltages of high speed applications. An internal oscillator sets n Parallel and Serial I/O Interface the conversion time, easing external timing considera- n 48-pin 7mm × 7mm LQFP and QFN Packages tions. The LTC2389-18 dissipates only 162.5mW at applicaTions 2.5Msps, while both nap and sleep power-down modes are provided to further reduce power consumption during n Medical Imaging inactive periods. n High Speed, Wide Dynamic Range Data Acquisition L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n Industrial Process Control SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 7705765. n Instrumentation n ATE Typical applicaTion32k Point FFT fSMPL = 2.5Msps, fIN = 2kHz 5V 1.8V TO 5V 0 SNR = 99.8dB 4.096V 10µF 0.1µF 0.1µF 10µF –20 THD = –116dB SINAD = 99.7dB 0V –40 SFDR = 117dB PARALLEL VDD OVDD 0V OR SERIAL 18 BIT –60 10Ω 49.9Ω INTERFACE IN+ 4.096V MODE0 –80 + 1nF MODE1 0V LTC2389-18 –100 RESET 4.096V PD – –120 1nF CS AMPLITUDE (dBFS) 10Ω 0V OB/2C IN– –140 PD/FD 49.9Ω 4.096V BUSY –160 VCM REFOUT REFIN REFSENSE GND CNVST SAMPLE 0V CLOCK –180 10µF 0 250 500 750 1000 1250 238918 TA01a 2.048V FREQUENCY (kHz) 1µF 238918 TA01b 238918f 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Analog Input Converter Characteristics Dynamic Accuracy Reference Characteristics Digital Inputs And Digital Outputs Power Requirements Timing Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Timing Diagrams Applications Information Package Description Typical Application Related Parts