CM2368 SAR ADC Synchronous sampling ADC 8-channel data acquisition system (DAS) with built-in 18 bit, bipolar input

Overview
The CM2368 is an 18-bit, 8-channel simultaneously sampled data acquisition system (DAS). Each channel integrates analog input clamp protection, a programmable gain amplifier (PGA), a low-pass filter (LPF), and an 18-bit SAR ADC. The device also includes a flexible digital filter, a low-drift 2.5 V reference, a reference buffer, and high-speed serial and parallel interfaces.

Operating from a single 5 V supply, the CM2368 supports true bipolar input ranges of ±12.5 V, ±10 V, ±5 V, and ±2.5 V in single-ended mode, and ±25 V, ±20 V, ±12.5 V, ±10 V, and ±5 V in differential mode. All channels can be sampled at throughput rates up to 1 MSPS. The input clamp protection withstands voltages up to ±19.5 V. A high input impedance of 1 MΩ together with on-chip filtering significantly simplifies external circuit design.

Features

• Bipolar analog input ranges:
  • Single-ended: ±12.5 V, ±10 V, ±5 V, ±2.5 V
  • Differential: ±25 V, ±20 V, ±12.5 V, ±10 V, ±5 V
• 5 V analog supply, 1.71 V to 5.25 V digital I/O supply
• 8-channel simultaneous sampling
• Performance:
  • Up to 7000 V ESD protection on analog inputs
  • 94.5 dB SNR (without oversampling), –107 dB THD
  • ±2 LSB INL, ±0.6 LSB DNL
• Flexible parallel/serial interface
• SPI / QSPI / MICROWIRE / DSP compatible
• Fully integrated data acquisition solution
• Analog input clamp protection
• Input buffer with 1 MΩ input impedance
• First-order anti-aliasing filter
• On-chip precision reference and buffer
• 18-bit, 1 MSPS ADC (all channels)
• Flexible digital filter with OSR up to 256×
• Two bandwidth options: 23 kHz and 202 kHz
• Low power: 175 mW (operating), 25 mW (standby)
• LQFP-64 (10 mm × 10 mm) package

Product list

SAR ADC