16/20-Bit, Multi-Range A/D Converters with 4-Bit Latch,16/20-Bit, Multi-Range A/D Converters with 4-Bit Latch

The 16-bit CS5525 and the 20-bit CS5526 are highly integrated Delta-Sigma A/D converters which include an instrumentation amplifier, a PGA (programmable gain amplifier), eight digital filters, and self and system calibration circuitry.

The converters are designed to provide their own negative supply which enables their on-chip instrumentation amplifiers to measure bipolar ground-referenced signals ¡Ü¡À100 mV. By directly supplying NBV with -2.5V and with VA+ at 5V, ¡À2.5V signals (with respect to ground) can be measured.

The digital filters provide programmable output update rates between 3.76 Hz to 202 Hz (XIN = 32.768 kHz). Output word rates can be increased by approximately 3X by using XIN = 100 kHz. Each filter is designed to settle to full accuracy for its output update rate in one conversion cycle. The filters with word rates of 15 Hz or less (XIN = 32.768 kHz) reject both 50 and 60 Hz (¡À3 Hz) line interference simultaneously.

Low power, single conversion settling time, programmable output rates, and the ability to handle negative input signals make these single supply products ideal solutions for isolated and non-isolated applications.

• Delta-Sigma A/D converter
  • Linearity error: 0.0015 FS
  • Noise-free resolution: 18-bits
• Bipolar/unipolar input ranges
  • 25 mV, 55 mV, 100 mV, 1V, 2.5V, and 5V
• Chopper-stabilized instrumentation amplifier
• On-chip charge pump drive circuitry
• Simple, three-wire serial interface
• Programmable output word rates
  • 3.76 Hz to 202 Hz (XIN = 32.768 kHz)
  • 11.47 Hz to 616 Hz (XIN = 100 kHz)
  • Output settles in one conversion cycle
• Simultaneous 50/60 Hz noise rejection
• System and self-calibration with read/write registers
• Single 5V analog supply; 3 or 5V digital supply
• Low power mode consumption: 4 mW
  • 1.8 mW in 1, 2.5, and 5V input ranges
• Package: 20-pin SSOP, 20-pin PDIP