LTC2451 Ultra-Tiny, 16-Bit ∆∑ ADC with I2C Interface FEATURESDESCRIPTION n GND to VCC Single-Ended Input Range The LTC®2451 is an ultra-tiny, 16-bit, analog-to-digital n 0.02LSB RMS Noise converter. The LTC2451 uses a single 2.7V to 5.5V sup- n 2LSB INL, No Missing Codes ply, accepts a single-ended analog input voltage and n 1LSB Offset Error communicates through an I2C interface. The converter n 4LSB Full-Scale Error is available in an 8-pin, 3mm × 2mm DFN or TSOT-23 n Programmable 30/60 Conversions per Second package. It includes an integrated oscillator that does not n Single Conversion Settling Time for Multiplexed require any external components. It uses a delta-sigma Applications modulator as a converter core and provides single-cycle n Single-Cycle Operation with Auto Shutdown settling time for multiplexed applications. The LTC2451 n 400µA Supply Current includes a proprietary input sampling scheme that re- n 0.2µA Sleep Current duces the average input sampling current several orders n Internal Oscillator—No External Components Required of magnitude lower than conventional ∆∑ converters. n Single Supply, 2.7V to 5.5V Operation The LTC2451 is capable of up to 60 conversions per n 2-Wire I2C Interface second and, due to the very large oversampling ratio, n Ultra-Tiny 3mm × 2mm DFN or TSOT-23 Package has extremely relaxed antialiasing requirements. In the 30Hz mode, the LTC2451 includes continuous internal APPLICATIONS offset calibration algorithms which are transparent to the n System Monitoring user, ensuring accur acy over time and over the operating n Environmental Monitoring temperature range. The converter has external REF+ and n Direct Temperature Measurements REF– pins and the input voltage can range from V – REF to n Instrumentation V + + – REF . If VREF = VCC and VREF = GND, the input voltage n Industrial Process Control can range from GND to VCC. n Data Acquisition n Following a single conversion, the LTC2451 can auto- Embedded ADC Upgrades matically enter sleep mode and reduce its power to less L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. No Latency ∆∑ and Easy Drive are trademarks of Linear Technology than 0.2µA. If the user reads the ADC once per second, Corporation. All other trademarks are the property of their respective owners. Protected by U.S. the LTC2451 consumes an average of less than 50µW Patents, including 6208279, 6411242, 7088280, 7164378. from a 2.7V supply. TYPICAL APPLICATIONIntegral Nonlinearity, VCC = 3V 3 2 2.7V TO 5.5V 0.1µF 10µF 1 REF+ VCC SCL 1k 0 TA = 90°C IN LTC2451 2-WIRE I2C INL (LSB) SENSOR SDA INTERFACE 0.1µF REF– GND –1 TA = –45°C, 25°C –2 2451 TA01a –3 0 0.5 1 1.5 2 2.5 3 INPUT VOLTAGE (V) 2451 TA01b 2451fg 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Analog Input And References Power Requirements I2C Inputs And Outputs I2C Timing Characteristics Typical Performance Characteristics Pin Functions Block Diagram Applications Information Typical Applications Package Description Revision History Typical Application Related Parts