Analog Devices Inc./Maxim Integrated

The LTC2498 is a 16-channel (8-differential) 24-bit No Latency ΔΣ™ADC with Easy Drive technology. The patented sampling scheme eliminates dynamic input current errors and the shortcomings of on-chip buffering through automatic cancellation of differential input current. This allows large external source impedances, and rail-to-rail input signals to be directly digitized while maintaining exceptional DC accuracy.The LTC2498 includes a high accuracy temperature sensor and an integrated oscillator. This device can be configured to measure an external signal (from combinations of 16 analog input channels operating in single ended or differential modes) or its internal temperature sensor. The integrated temperature sensor offers 1/30th °C resolution and 2°C absolute accuracy.The LTC2498 allows a wide common mode input range (0V to VCC), independent of the reference voltage. Any combination of single-ended or differential inputs can be selected and the first conversion after a new channel is selected is valid. Access to the multiplexer output enables optional external amplifiers to be shared between all analog inputs and auto calibration continuously removes their associated offset and drift.ApplicationsDirect Sensor DigitizerDirect Temperature MeasurementInstrumentationIndustrial Process Control

The LTC2508-32 is a low noise, low power, high-performance 32-bit ADC with an integrated configurable digital filter. Operating from a single 2.5V supply, the LTC2508-32 features a fully differential input range up to ±VREF, with VREFranging from 2.5V to 5.1V. The LTC2508-32 supports a wide common mode range from 0V to VREFsimplifying analog signal conditioning requirements.The LTC2508-32 simultaneously provides two output codes: (1) a 32-bit digitally filtered high precision low noise code, and (2) a 22-bit no latency composite code. The configurable digital filter reduces measurement noise by lowpass filtering and down-sampling the stream of data from the SAR ADC core, giving the 32-bit filtered output code. The 22-bit composite code consists of a 14-bit code representing the differential voltage and an 8-bit code representing the common mode voltage. The 22-bit composite code is available each conversion cycle, with no cycle of latency.The digital filter can be easily configured for 4 different down-sampling factors by pin strapping. The configurations provide a dynamic range of 131dB at 3.9ksps and 145dB at 61sps. The digital lowpass filter relaxes the requirements for analog anti-aliasing. Multiple LTC2508-32 devices can be easily synchronized using the SYNC pin.ApplicationsSeismologyEnergy ExplorationAutomated Test Equipment (ATE)High-Accuracy Instrumentation