Linear Technology Corp. introduces the LTC2338-18, an 18-bit 1 Msps no latency analog-to-digital converter (ADC) with a wide ±10.24 V fully differential, true bipolar input range for high voltage, industrial applications. The device operates from a single 5V supply, achieves 100 dB SNR and -110 dB THD and features an internal 2.048 V (20 ppm/°C max) reference and reference buffer. An input divider network scales and level shifts the input signal, eliminating complicated circuitry required to directly interface true bipolar signals. 

The LTC2338-18 leads a pin- and software-compatible family of 18-bit serial SPI SAR ADCs with speeds ranging from 250 ksps to 1 Msps. A pin-compatible 16-bit and 18-bit family with pseudo differential true bipolar inputs (LTC2328-18) will also be available. The proprietary internal reference buffer maintains less than 1LSB error during sudden burst of conversions, enabling true one-shot operation after lengthy idle periods. These ADCs operate from a single 5V supply and consume just 50mW at 1Msps. Power further reduces linearly at slower sample rates. A shutdown mode dissipates only 300µW when idle.

The DC1908A demonstration board enables easy evaluation of the LTC2338 family in conjunction with the DC590B (QuikEval™) or DC718C (PScope™) data collection boards. The fully differential LTC2338-18 and pseudo differential LTC2328-18 families are available in small MSOP-16 packages in commercial, industrial and automotive temperature grades. Pricing begins at $29.10 in 1,000 piece quantities. For more information, visit www.linear.com/product/LTC2338.

Summary of Features: LTC2338-18:

  • 1Msps Throughput Rate

  • ±4LSB INL Max

  • Fully Differential Inputs 

  • True Bipolar Input Ranges ±6.25V, ±10.24V, ±12.5V

  • 100dB SNR (Typ) at fIN = 2kHz

  • –110dB THD (Typ) at fIN = 2kHz

  • Guaranteed Operation to 125°C

  • 5V Supply

  • Low Drift (20ppm/°C Max) 2.048V Internal Reference

  • Onboard Single-Shot Capable Reference Buffer

  • 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 

  • Power Dissipation 50mW (Typ)

  • 16-Lead MSOP Package