ADS1258IPHPREP

The ADS1258 is a 16-channel (multiplexed), low-noise, 24-bit, delta-sigma (ΔΣ) analog-to-digital converter (ADC) that provides single-cycle settled data at channel scan rates from 1.8k to 23.7k samples per second (SPS) per channel. A flexible input multiplexer accepts combinations of eight differential or 16 single-ended inputs with a full-scale differential range of 5 V or true bipolar range of ±2.5 V when operating with a 5-V reference. The fourth-order delta-sigma modulator is followed by a fifth-order sinc digital filter optimized for low-noise performance. The differential output of the multiplexer is accessible to allow signal conditioning prior to the input of the ADC. Internal system monitor registers provide supply voltage, temperature, reference voltage, gain, and offset data. An onboard PLL generates the system clock from a 32.768-kHz crystal, or can be overridden by an external clock source. A buffered system clock output (15.7 MHz) is provided to drive a microcontroller or additional converters. Serial digital communication is handled via an SPI-compatible interface. A simple command word structure controls channel configuration, data rates, digital I/O, monitor functions, etc. Programmable sensor bias current sources can be used to bias sensors or verify sensor integrity. The ADS1258 operates from a unipolar 5-V or bipolar ±2.5 V analog supply and a digital supply compatible with interfaces ranging from 2.7 V to 5.25 V. The ADS1258 is available in QFN-48 and QFP-48 packages.

Applications

• Medical
• Process Control
• Machine and System Monitoring
• Fast Scan Multi-Channel Instrumentation
• Industrial Systems
• Test and Measurement Systems

Key features

• 24 Bits, No Missing Codes
• Fixed-Channel or Automatic Channel Scan
• Fixed-Channel Data Rate: 125 kSPS
• Auto-Scan Data Rate: 23.7 kSPS/Channel
• Single-Conversion Settled Data
• 16 Single-Ended or 8 Differential Inputs
• Unipolar (5 V) or Bipolar (±2.5 V) Operation
• Low Noise: 2.8 μV_RMS at 1.8 kSPS
• 0.0003% Integral Nonlinearity
• DC Stability (typical): 0.02 μV/°C Offset Drift, 0.4 ppm/°C Gain Drift
• Open-Sensor Detection
• Conversion Control Pin
• Multiplexer Output for External Signal Conditioning
• On-Chip Temperature, Reference, Offset, Gain, and Supply Voltage Readback
• 42-mW Power Dissipation
• Standby, Sleep, and Power-Down Modes
• 8 General-Purpose Inputs/Outputs (GPIO)
• 32.768-kHz Crystal Oscillator or External Clock