16bit delta-sigma ADC ups system accuracy

Linear Technology Corp. introduces the LTC2450, a 16bit delta-sigma ADC in an ultra-tiny 2-by-2mm DFN package that enables performance upgrades to lower resolution systems.

Designers of portable and space-constrained applications typically tradeoff space with performance, leading to use of MCUs with internal ADCs or lower resolution ADCs with preamplifier circuitry. These designs are typically complex and lag in performance due to larger linearity errors, greater noise or other unguaranteed specifications.

In just 4mm? area, the versatile LTC2450 achieves excellent 16bit DC performance of 2LSB integral nonlinearity error, 1.4?V_RMS noise and 0.01 percent gain error. The tiny size and guaranteed 16bit resolution allows designers to easily replace an embedded system's integrated ADC or a lower performance ADC and its preamplifier circuitry.

Using the 2.7-5.5V supply voltage as reference, LTC2450 draws just 500?A of supply current, minimizing power loss. After automatically entering a shutdown mode, supply current is reduced to less than 1?A, further preserving battery power. By controlling the duration between conversions, LTC2450's power dissipation can be reduced to 50?W at a 1Hz output rate. An internal oscillator allows conversion rates up to 30Hz/s, making it easy to measure temperature, pressure, voltage or other low-frequency sensor outputs.

LTC2450 communicates via a simple three-wire SPI-compatible interface while measuring a single-ended analog input that may extend from ground to Vcc. LTC2450 includes continuous internal offset and full-scale calibration of the input signal, ensuring accuracy over time and over the full operating temperature range. Linear Technology's No Latency Delta Sigma design allows the ADC to multiplex several inputs with no delay in reading the output data. The device incorporates a proprietary sampling network that reduces the input sampling current to less than 50nA, enabling a wide range of input protection and filter circuits.

LTC2450 is available in both commercial and industrial temperature grade versions, with pricing beginning at $1.15 each in 1,000-piece quantities.