Two output codes are provided simultaneously on the LTC2500-32, a 32-bit digitally filtered high precision low noise code, and a 32-bit no latency composite code. The configurable digital filter reduces measurement noise by lowpass filtering and downsampling the stream of data from the SAR ADC core, resulting in the 32-bit filtered output code. The 32-bit composite code consists of an overrange detection bit, a 24-bit code specifying the differential input voltage and a 7-bit code rendering the common mode input voltage. The 32-bit composite code is available in each conversion cycle, eliminating a cycle of latency.
Using the SPI-compatible interface, the digital filter is highly configurable and features many distinct filter types that are ideal for a wide range of applications. The digital lowpass filter relaxes the requirements for analog anti-aliasing. Utilizing the SYNC pin, multiple LTC2500-32 devices can be easily synchronized.