ADI AD7714YNZ

The AD7714 is a complete analog front end for low- frequency measurement applications. The device accepts low level signals directly from a transducer and outputs a serial digital word. It employs a sigma- delta conversion technique to realize up to 24 bits of no missing codes performance. The input signal is applied to a proprietary programmable gain front end based around an analog modulator. The modulator output is processed by an on- chip digital filter. The first notch of this digital filter can be programmed via the on- chip control register allowing adjustment of the filter cutoff and settling time.

The part features three differential analog inputs (which can also be configured as five pseudo- differential analog inputs) as well as a differential reference input. It operates from a single supply (+3V or +5V). The AD7714 thus performs all signal conditioning and conversion for a system consisting of up to five channels.

The AD7714 is ideal for use in smart, microcontroller- or DSP systems. It features a serial interface that can be configured for three- wire operation. Gain settings, signal polarity and channel selection can be configured in software using the serial port. The AD7714 provides self- calibration, system calibration and background calibration options and also allows the user to read and write the on- chip calibration registers.

CMOS construction ensures very low power dissipation, and the power- down mode reduces the standby power consumption to 15μW typ. The part is available in a 24- pin, 0.3 inch- wide, plastic dual- in- line package (DIP); a 24- lead small outline (SOIC) package, a 28- lead shrink small outline package (SSOP) and a 24- lead thin shrink small outline package (TSSOP).

• Charge Balancing ADO
• 24 Bits No Missing Codes
• 0.0015% Nonlinearity
• Five- Channel Programmable Gain Front End Gains from 1 to 128
• Can Be Configured as Three Fully Differential Inputs or Five Pseudo- Differential Inputs
• Three- Wire Serial Interface, SPI, QSPI, MICROWIRE and DSP Compatible
• 3 V (AD7714- 3) or 5 V (AD7714- 5) Operation
• Low Noise (<150 nV rms)
• Low Current (350 μA typ) with Power- Down (5 μA typ)
• AD7714Y Grade: +2.7 V to 3.3 V or +4.75 V to +5.25 V Operation
• 0.0010% Linearity Error
• • 40℃ to +105℃ Temperature Range
• Schmitt Trigger on SCLK and DIN
• Low Current (226 μA typ) with Power- Down (4 μA typ)
• Lower Power Dissipation than Standard AD7714
• Available in 24- Lead TSSOP Package
• Low- Pass Filter with Programmable Filter Cutoffs
• Ability to Read/Write Calibration Coefficients

• Portable Industrial Instruments
• Portable Weigh Scales
• Loop- Powered Systems
• Pressure Transducers