AD7783 Datasheet | Analog Devices

a Features 2-Channel, 24-Bit ⌺- ⌬ ADC Pin Configurable (No Programmable Registers) Pin Selectable Input Channels Pin Programmable Input Ranges (؎2.56 V or ؎160 m V) Fixed 19.79 Hz Update Rate Simultaneous 50 Hz and 60 Hz Rejection ISOURCE Select™ 24-Bit No Missing Codes 18.5-Bit p-p Resolution (؎2.56 V Range) 16.5-Bit p-p Resolution (؎160 m V Range) INTERFACE Master or Slave Mode of Operation Slave Mode 3-Wire Serial SPI™, QSPI™, MICROWIRE™, and DSP-patible Schmitt Trigger on SCLK POWER Specified for Single 3 V and 5 V Operation Normal: 1.3 m A@ 3 V Power-Down: 9 ␮ A .. Read Only, Pin Configured 24-Bit ⌺-⌬ ADC AD7783 FUNCTIONAL BLOCK DIAGRAM IEXC1 200␮A REFIN(+) REFIN(- ) XTAL1 XTAL2 IEXC2 200␮A IOUT1 IOUT2 IPIN OSCILLATOR AND PLL AIN(+) AIN(- ) 24-BIT ⌺-⌬ ADC SERIAL INTERFACE AND CONTROL LOGIC DOUT/RDY SCLK MODE RANGE BASIC CONNECTION DIAGRAM POWER SUPPLY VDD ON-CHIP FUNCTIONS Rail-Rail Input Buffer and PGA APPLICATIONS Sensor Measurement Industrial Process Control Temperature Measurement Pressure Measurements Weigh Scales Portable Instrumentation GENERAL DESCRIPTION ANALOG INPUT CURRENT SOURCES REFERENCE INPUT AIN(+) AIN(- ) IOUT1 IOUT2 CS DOUT/RDY SCLK XTAL1 REFIN(+) REFIN(- ) GND XTAL2 32.768k Hz CRYSTAL DIGITAL INTERFACE The AD7783 is a plete analog front end for low-frequency measurement applications. The 24-bit sigma-delta ADC contains one fully differential input channel that can be configured with a gain of 1 or 16 allowing full-scale input signal ranges of ± 2.56 V or ± 160 m V from a +2.5 V differential reference input. It also contains two 200 µA integrated current sources. The AD7783 has an extremely simple, read-only digital interface which can be operated in master mode or slave mode. There are no on-chip registers to be programmed. The input signal range and current source selection are configured using two external pins. ISOURCE Select is a trademark of Analog Devices, Inc....