LTC2508-32 Series

32-Bit Over-Sampling ADC with Configurable Digital Filter

Catalog

32-Bit Over-Sampling ADC with Configurable Digital Filter

Part	Input Type	Number of Bits	Voltage - Supply, Analog [Max]	Voltage - Supply, Analog [Min]	Data Interface	Reference Type	Mounting Type	Architecture	Ratio - S/H:ADC	Number of Inputs	Voltage - Supply, Digital [Min]	Voltage - Supply, Digital [Max]	Sampling Rate (Per Second)	Package / Case	Supplier Device Package	Operating Temperature [Max]	Operating Temperature [Min]	Number of A/D Converters	Configuration
Analog Devices LTC2508CDKD-32#PBF	Differential Pseudo-Differential	32	2.625 V	2.375 V	SPI	External	Surface Mount	SAR	1:1	1	2.375 V	2.625 V	1 M	24-WFDFN Exposed Pad	24-DFN (7x4)	70 °C	0 °C	1	S/H-ADC

Catalog

32-Bit Over-Sampling ADC with Configurable Digital Filter

Key Features

• ±0.5ppm INL (Typ)

• 145dB Dynamic Range (Typ) at 61sps

• 131dB Dynamic Range (Typ) at 4ksps

• Guaranteed 32-Bits No Missing Codes

• Configurable Digital Filter with SynchronizationRelaxed Anti-Aliasing Filter Requirements

• Relaxed Anti-Aliasing Filter Requirements

• Dual Output 32-Bit SAR ADC32-Bit Digitally Filtered Low Noise Output14-Bit Differential + 8-Bit Common Mode 1Msps No Latency Output

• 32-Bit Digitally Filtered Low Noise Output

• 14-Bit Differential + 8-Bit Common Mode 1Msps No Latency Output

• Wide Input Common-Mode Range

• Guaranteed Operation to 85°C

• 1.8V to 5V SPI-Compatible Serial I/O

• Low Power: 24mW at 1Msps

• 24-Lead 7mm × 4mm DFN Package

Description

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