link to page 1 link to page 1 link to page 1 link to page 1 link to page 3 link to page 4 link to page 6 link to page 7 link to page 7 link to page 7 link to page 8 link to page 10 link to page 13 link to page 14 link to page 14 link to page 14 link to page 15 link to page 15 link to page 16 link to page 16 link to page 16 link to page 16 link to page 17 link to page 18 link to page 18 link to page 19 link to page 20 link to page 21 link to page 21 link to page 22 link to page 23 link to page 24 link to page 24 link to page 24 link to page 25 link to page 25 AD7298TABLE OF CONTENTS Features .. 1 Temperature Sensor Averaging .. 14 General Description ... 1 VDRIVE.. 15 Functional Block Diagram .. 1 The Internal or External Reference.. 15 Product Highlights ... 1 Control Register.. 16 Revision History ... 2 Modes of Operation ... 17 Specifications... 3 Traditional Multichannel Mode of Operation.. 17 Timing Specifications .. 5 Repeat Operation ... 18 Absolute Maximum Ratings.. 6 Power-Down Modes .. 19 ESD Caution.. 6 Powering Up the AD7298 ... 20 Thermal Resistance .. 6 Reset ... 20 Pin Configuration and Function Description .. 7 Serial Interface .. 21 Typical Performance Characteristics ... 9 Temperature Sensor Read ... 22 Terminology .. 12 Layout and Configuration... 23 Circuit Information .. 13 Power Supply Bypassing and Grounding.. 23 Converter Operation.. 13 Temperature Monitoring... 23 Analog Input ... 13 Outline Dimensions ... 24 Temperature Sensor Operation .. 14 Ordering Guide .. 24 REVISION HISTORY6/11—Rev. A to Rev. B Changes to Internal Temperature Sensor, Accuracy Parameter in Table 1.. 3 1/11—Rev. 0 to Rev. A Removed Input Impedance Parameter .. 3 Added Input Capacitance Parameter of 8 pF.. 3 Changes to Figure 11.. 10 Changed C1 Value to 8 pF in Analog Input Section.. 13 Changes to Figure 23.. 14 Changes to Ordering Guide .. 24 9/10—Revision 0: Initial Version Rev. B | Page 2 of 24 Document Outline FEATURES GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION THERMAL RESISTANCE PIN CONFIGURATION AND FUNCTION DESCRIPTION TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY CIRCUIT INFORMATION CONVERTER OPERATION ANALOG INPUT ADC Transfer Function TEMPERATURE SENSOR OPERATION TEMPERATURE SENSOR AVERAGING Temperature Value Format VDRIVE THE INTERNAL OR EXTERNAL REFERENCE CONTROL REGISTER MODES OF OPERATION TRADITIONAL MULTICHANNEL MODE OF OPERATION REPEAT OPERATION POWER-DOWN MODES Normal Mode Partial Power-Down Mode Full Power-Down Mode POWERING UP THE AD7298 RESET SERIAL INTERFACE TEMPERATURE SENSOR READ LAYOUT AND CONFIGURATION POWER SUPPLY BYPASSING AND GROUNDING TEMPERATURE MONITORING OUTLINE DIMENSIONS ORDERING GUIDE