The LTC2389-18 is a low noise, high speed 18-bit successive approximation register (SAR) ADC. Operating from a single 5V supply, the LTC2389-18 supports pin-configurable fully differential (±4.096V), pseudo-differential unipolar (0V to 4.096V), and pseudo-differential bipolar (±2.048V) analog input ranges, allowing it to interface with multiple signal chain formats without requiring additional level translation or signal conditioning. The LTC2389-18 achieves ±3LSB INL (maximum), no missing codes at 18-bits, and 99.8dB (fully differential)/95.2dB (pseudo differential) SNR (typical). The LTC2389-18 includes a precision internal 4.096V reference, with a guaranteed 0.5% initial accuracy and a ±20ppm/°C (maximum) temperature coefficient, as well as an internal reference buffer. Fast 2.5Msps throughput with no cycle latency in the parallel interface modes makes the LTC2389-18 ideally suited for a wide variety of high speed applications. An internal oscillator sets the conversion time, easing external timing considerations. The LTC2389-18 dissipates only 162.5mW at 2.5Msps, while both nap and sleep power-down modes are provided to further reduce power consumption during inactive periods.