Cirrus Logic CS5531-ASZ

The CS5531/32/33/34 are highly integrated ΔΣ Analog-to-Digital Converters (ADCs) which use charge-balance techniques to achieve 16-bit (CS5531/33) and 24-bit (CS5532/34) performance. The ADCs are optimized for measuring low-level unipolar or bipolar signals in weigh scale, process control, scientific, and medical applications. To accommodate these applications, the ADCs come as either two-channel (CS5531/32) or four-channel (CS5533/34) devices and include a very low noise chopper-stabilized instrumentation amplifier (6nV/√Hz @ 0.1 Hz) with selectable gains of 1x, 2x, 4x, 8x, 16x, 32x, and 64x. These ADCs also include a fourth order ΔΣ modulator followed by a digital filter which provides twenty selectable output word rates of 6.25, 7.5, 12.5, 15, 25, 30, 50, 60, 100, 120, 200, 240, 400, 480, 800, 960, 1600, 1920, 3200, and 3840 Sps (MCLK = 4.9152 MHz). To ease communication between the ADCs and a microcontroller, the converters include a simple three-wire serial interface which is SPI and Microwire compatible with a Schmitt-trigger input on the serial clock (SCLK). High dynamic range, programmable output rates, and flexible power supply options makes these ADCs ideal solutions for weigh scale and process control applications.

• Chopper-stabilized PGIA (Programmable Gain Instrumentation Amplifier, 1x to 64x) – 12 nV/√Hz @ 0.1 Hz (No 1/f noise) at 64x 1200 pA Input Current with Gains >1
• Delta-sigma Analog-to-digital Converter – Linearity Error: 0.0007% FS – Noise Free Resolution: Up to 23 bits
• Two- or Four-channel Differential MUX
• Scalable Input Span via Calibration – ±5 mV to differential ±2.5 V
• Scalable VREF Input: Up to Analog Supply
• Simple Three-wire Serial Interface SPI and Microwire Compatible – Schmitt Trigger on Serial Clock (SCLK)
• R/W Calibration Registers Per Channel
• Selectable Word Rates: 6.25 to 3,840 Sps
• Selectable 50 or 60 Hz Rejection
• Power Supply Configurations – VA+ = +5 V; VA- = 0 V; VD+ = +3 V to +5 V – VDA+ = +2.5 V; VA- = -2.5 V; VD+ = +3 V to +5 V VA+ = +3 V; VA- = -3 V; VD+ = +3 V

• weigh scale
• process control
• scientific
• medical