Features

• 500ksps Throughput Rate
• ±1.75LSB INL (Max)
• Guaranteed 18-Bit No Missing Codes
• Low Power: 6.8mW at 500ksps, 6.8μW at 500sps
• 102dB SNR (Typ) at f_IN = 2kHz
• –124dB THD (Typ) at f_IN = 2kHz
• Digital Gain Compression (DGC)
• Guaranteed Operation to 125°C
• 2.5V Supply
• Fully Differential Input Range ±V_REF
• V_REF Input Range from 2.5V to 5.1V
• No Pipeline Delay, No Cycle Latency
• 1.8V to 5V I/O Voltages
• SPI-Compatible Serial I/O with Daisy-Chain Mode
• Internal Conversion Clock
• 16-Lead MSOP and 4mm × 3mm DFN Packages

Typical Application

Description

The LTC®2377-18 is a low noise, low power, high speed 18-bit successive approximation register (SAR) ADC. Operating from a 2.5V supply, the LTC2377-18 has a ±V_REF fully differential input range with V_REF ranging from 2.5V to 5.1V. The LTC2377-18 consumes only 6.8mW and achieves ±1.75LSB INL maximum, no missing codes at 18 bits with 102dB SNR.

The LTC2377-18 has a high speed SPI-compatible serial interface that supports 1.8V, 2.5V, 3.3V and 5V logic while also featuring a daisy-chain mode. The fast 500ksps throughput with no cycle latency makes the LTC2377-18 ideally suited for a wide variety of high speed applications. An internal oscillator sets the conversion time, easing external timing considerations. The LTC2377-18 automatically powers down between conversions, leading to reduced power dissipation that scales with the sampling rate.

The LTC2377-18 features a unique digital gain compression (DGC) function, which eliminates the driver amplifier’s negative supply while preserving the full resolution of the ADC. When enabled, the ADC performs a digital scaling function that maps zero-scale code from 0V to 0.1 • V_REF and full-scale code from V_REF to 0.9 • V_REF. For a typical reference voltage of 5V, the full-scale input range is now 0.5V to 4.5V, which provides adequate headroom for powering the driving amplifier from a single 5.5V supply.