Breakthrough 0.5ppm INL, 1Msps, No Latency SAR ADC Achieves True 20-Bit Precision

Supplied by
  1. Analog Devices Ltd

    Breakthrough 0.5ppm INL, 1Msps, No Latency SAR ADC Achieves True 20-Bit Precision
    The LTC2378-20 is a 20-bit 1Msps no latency successive approximation register (SAR) analog-to-digital converter with exceptionally low 0.5ppm (typ) and 2ppm (max) Integral Non-Linearity (INL) error.INL is a key specification in precision applications, such as seismic monitoring and semiconductor fabrication, indicating how much the ADC transfer function deviates from its ideal. Since linearity effectively cannot be calibrated at the system level, the ADC's INL specification often sets the overall system accuracy.The best-in-class 0.5ppm INL of the LTC2378-20 enables a new generation of precision systems with true 20-bit accuracy. The proprietary architecture leads to an extremely stable 2ppm (max) INL and -114dB THD (max) over the device's entire operating range of -40°C to 85°C.The LTC2378-20 achieves the industry's highest signal-to-noise ratio (SNR) of 104dB for a 1Msps no latency ADC. The wide dynamic range and true 20-bit resolution reduce or eliminate the need for additional gain in the signal chain, thereby improving total system accuracy and noise. Fast 1Msps throughput with no latency enables the use of multiplexers to replace costly, independent ADCs with slower throughputs, thus reducing system cost and complexity.The LTC2378-20 is the leadership product in a pin- and software-compatible family of 20/18/16-bit SAR ADCs with speeds ranging from 250ksps up to 2Msps with serial SPI interfaces. The family operates from a 2.5V supply, with a ±5V fully differential input range using an external 5V reference.The DC1925A evaluation kit demonstrates the 0.5ppm INL and 104dB SNR performance of the LTC2378-20. The LTC2378-20, LTC2377-20 and the LTC2376-20 are available in small MSOP-16 and 4mm x 3mm DFN-16 packages, priced starting at $29.50, $25.50 and $18.17 each, respectively, in 1,000 piece quantities.