Features

• 400ksps per Channel Throughput
• Four Simultaneous Sampling Channels
• ±4LSB INL (Maximum, ±4.096V Range)
• Guaranteed 18-Bit, No Missing Codes
• Differential, Wide Common Mode Range Inputs
• Per-Channel SoftSpan Input Ranges:
    ±4.096V, 0V to 4.096V, ±2.048V, 0V to 2.048V
    ±5V, 0V to 5V, ±2.5V, 0V to 2.5V
• 95dB Single-Conversion SNR (Typical)
• −114dB THD (Typical) at f_IN = 2kHz
• 102dB CMRR (Typical) at f_IN = 200Hz
• Rail-to-Rail Input Overdrive Tolerance
• Guaranteed Operation to 125°C
• Integrated Reference and Buffer (4.096V)
• SPI CMOS (1.8V to 5V) and LVDS Serial I/O
• Internal Conversion Clock, No Cycle Latency
• 81mW Power Dissipation (Typical)
• 32-Lead (5mm × 5mm) QFN Package

Typical Application

Description

The LTC2344-18 is an 18-bit, low noise 4-channel simultaneous sampling successive approximation register (SAR) ADC with differential, wide common mode range inputs. Operating from a 5V supply and using the internal reference and buffer, each channel of this SoftSpan TM ADC can be independently configured on a conversion-by-conversion basis to accept ±4.096V, 0V to 4.096V, ±2.048V, or 0V to 2.048V signals. Individual channels may also be disabled to increase throughput on the remaining channels.

The wide input common mode range and 102dB CMRR of the LTC2344-18 analog inputs allow the ADC to directly digitize a variety of signals, simplifying signal chain design. This input signal flexibility, combined with ±4LSB INL, no missing codes at 18 bits, and 95dB SNR, makes the LTC2344-18 an ideal choice for many applications requiring wide dynamic range.

The LTC2344-18 supports pin-selectable SPI CMOS (1.8V to 5V) and LVDS serial interfaces. Between one and four lanes of data output may be employed in CMOS mode, allowing the user to optimize bus width and throughput.