The LTC23500-32 are low noise, low power, high performance 32-bit ADCs from Linear Technology with an integrated configurable digital filter. Operating from a single 2.5 V supply, they feature a fully differential input range up to ±VREF, with VREF ranging from 2.5 V to 5.1 V. Supporting a wide common mode range from 0 V to VREF simplifying analog signal conditioning requirements.
The LTC23500-32 simultaneously provides two output codes: (1) a 32-bit digitally filtered high precision low noise code, and (2) a 32-bit no latency composite code. The configurable digital filter reduces measurement noise by low pass filtering and down-sampling the stream of data from the SAR ADC core, giving the 32-bit filtered output code. The 32-bit composite code consists of an overrange detection bit, a 24-bit code representing the differential input voltage and a 7-bit code representing the common mode input voltage. The 32-bit composite code is available each conversion cycle, with no cycle of latency.
The digital filter is highly configurable through the SPI compatible interface and features many distinct filter types that suit a variety of applications. The digital low pass filter relaxes the requirements for analog anti-aliasing. Multiple LTC2500 devices can be easily synchronized using the SYNC pin.
- ±0.5 ppm INL (Typ)
- 104 dB SNR (Typ) at 1 Msps
- 148 dB dynamic range (Typ) at 61 sps
- Guaranteed 32-bits no missing codes
- Configurable digital filter with synchronization
- Relaxed anti-aliasing filter requirements
- Dual output 32-bit SAR ADC
- 32-bit digitally filtered low noise output
- 24-bit differential + 7-bit common mode 1 Msps output with overrange detection
- Wide input common-mode range
- Guaranteed operation to 85°C
- 1.8 V to 5 V SPI-compatible serial I/O
- Low power: 24 mW at 1 Msps
- 24-lead 7 mm × 4 mm DFN packages
- Energy exploration
- Automatic test equipment
- High accuracy instrumentation
Video: 32-Bit Over-Sampling ADC with Configurable Digital Filter