Features

• 8-/16-Channel Single-Ended or 4-/8-Channel Differential Inputs (LTC2414/LTC2418)
• Low Supply Current (200µA Plus 4µA Autosleep)
• Differential Input and Differential Reference with GND to V_CC Common Mode Range
• 2ppm INL, No Missing Codes
• 2.5ppm Full-Scale Error and 0.5ppm Offset
• 0.2ppm Noise
• No Latency: Digital Filter Settles in a Single Cycle. Each Conversion Is Accurate, Even After a New Channel is Selected
• Single Supply 2.7V to 5.5V Operation
• Internal Oscillator—No External Components Required
• 110dB Min, 50Hz/60Hz Notch Filter

Typical Application

Description

The LTC2414/LTC2418 are 8-/16-channel (4-/8-differential) micropower 24-bit Delta Ssigma analog-to-digital converters. They operate from 2.7V to 5.5V and include an integrated oscillator, 2ppm INL and 0.2ppm RMS noise. They use delta-sigma technology and provide single cycle settling time for multiplexed applications. Through a single pin, the LTC2414/LTC2418 can be configured for better than 110dB differential mode rejection at 50Hz or 60Hz ±2%, or they can be driven by an external oscillator for a user-defined rejection frequency. The internal oscillator requires no external frequency setting components.

The LTC2414/LTC2418 accept any external differential reference voltage from 0.1V to V_CC for flexible ratiometric and remote sensing measurement applications. They can be configured to take 4/8 differential channels or 8/16 single-ended channels. The full-scale bipolar input range is from -5V_REF to 0.5V_REF. The reference common mode voltage, V_REFCM, and the input common mode voltage, V_INCM, may be independently set within GND to V_CC. The DC common mode input rejection is better than 140dB.

The LTC2414/LTC2418 communicate through a flexible 4-wire digital interface that is compatible with SPI and MICROWIRE protocols.