RT2378-20 Radiation Tolerant 20-Bit, 1Msps, Low Power Plastic Package SAR ADC FeaTuresDescripTion n 10kRad (Si) Total Ionizing Dose (TID) per The RT2378-20 is a low noise, low power, high speed MIL-STD-883 TM1019 Condition A 20-bit successive approximation register (SAR) ADC. n Single Event Latch-Up (SEL) Threshold Linear Operating from a 2.5V supply, the RT2378-20 has a ±VREF Energy Transfer (LET) ≥ 30.86MeV-cm2/mg at fully differential input range with VREF ranging from 2.5V to TCASE = 70°C 5.1V. The RT2378-20 consumes only 21mW and achieves n Processed Using MIL-PRF-38535 Class N and ±2ppm INL maximum, no missing codes at 20 bits with PEM-INST-001 as a Guideline 104dB SNR. n TID and SEL Reports Available The RT2378-20 has a high speed SPI-compatible serial n 1Msps Throughput Rate interface that supports 1.8V, 2.5V, 3.3V and 5V logic n ±0.5ppm INL (Typ) while also featuring a daisy-chain mode. The fast 1Msps n Guaranteed 20-Bit No Missing Codes throughput with no cycle latency makes the RT2378-20 n Low Power: 21mW at 1Msps, 21µW at 1ksps ideally suited for a wide variety of high speed applications. n 104dB SNR (Typ) at fIN = 2kHz An internal oscillator sets the conversion time, easing ex- n –125dB THD (Typ) at fIN = 2kHz ternal timing considerations. The RT2378-20 automatically n Digital Gain Compression (DGC) powers down between conversions, leading to reduced n 2.5V Supply power dissipation that scales with the sampling rate. n Fully Differential Input Range ±VREF n V The RT2378-20 features a unique digital gain compression REF Input Range from 2.5V to 5.1V n No Pipeline Delay, No Cycle Latency (DGC) function, which eliminates the driver amplifier’s n 1.8V to 5V I/O Voltages negative supply while preserving the full resolution of the n SPI-Compatible Serial I/O with Daisy-Chain Mode ADC. When enabled, the ADC performs a digital scaling n Internal Conversion Clock function that maps zero-scale code from 0V to 0.1 • VREF n 16-Lead MSOP Package and full-scale code from VREF to 0.9 • VREF. For a typical reference voltage of 5V, the full-scale input range is now L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and SoftSpan is a trademark of Analog Devices, Inc. All other trademarks are the property of their 0.5V to 4.5V, which provides adequate headroom for respective owners. Patents Pending. Protected by U.S. Patents, including 7705765, 7961132, 8319673. powering the driving amplifier from a single 5.5V supply. 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 0.5 REF 10Ω 6800pF + RDL/SDI IN+ 0V SDO 0 V 3300pF RT2378-20 SCK REF – BUSY –0.5 IN– CNV SAMPLE CLOCK INL ERROR (ppm) 0V 10Ω 6800pF REF GND REF/DGC VREF –1.0 2.5V TO 5.1V RT237820 TA01a –1.5 47µF (X7R, 1210 SIZE) –2.0 0 262144 524288 786432 1048576 OUTPUT CODE RT237820 TA01b rt237820fa For more information www.linear.com 1 Document Outline Features 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