Features

• GND to V_CC Single-Ended Input Range
• 0.02LSB RMS Noise
• 2LSB INL, No Missing Codes
• 1LSB Offset Error
• 4LSB Full-Scale Error
• Programmable 30/60 Conversions per Second
• Single Conversion Settling Time for Multiplexed Applications
• Single-Cycle Operation with Auto Shutdown
• 400μA Supply Current
• 0.2μA Sleep Current
• Internal Oscillator—No External Components Required
• Single Supply, 2.7V to 5.5V Operation
• 2-Wire I²C Interface
• Ultra-Tiny 3mm × 2mm DFN or TSOT-23 Package

Typical Application

Description

The LTC2451 is an ultra-tiny, 16-bit, analog-to-digital converter. The LTC2451 uses a single 2.7V to 5.5V supply, accepts a single-ended analog input voltage and communicates through an I²C interface. The converter is available in an 8-pin, 3mm × 2mm DFN or TSOT-23 package. It includes an integrated oscillator that does not require any external components. It uses a delta-sigma modulator as a converter core and provides single-cycle settling time for multiplexed applications. The LTC2451 includes a proprietary input sampling scheme that reduces the average input sampling current several orders of magnitude lower than conventional ΔΣ converters.

The LTC2451 is capable of up to 60 conversions per second and, due to the very large oversampling ratio, has extremely relaxed antialiasing requirements. In the 30Hz mode, the LTC2451 includes continuous internal offset calibration algorithms which are transparent to the user, ensuring accuracy over time and over the operating temperature range. The converter has external REF⁺ and REF^– pins and the input voltage can range from V_REF ^– to V_REF ^+. If V_REF ⁺ = V_CC and V_REF ^– = GND, the input voltage can range from GND to V_CC.

Following a single conversion, the LTC2451 can automatically enter sleep mode and reduce its power to less than 0.2μA. If the user reads the ADC once per second, the LTC2451 consumes an average of less than 50μW from a 2.7V supply.