Datasheet AD7656A-1 (Analog Devices) - 7

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AD7656A-1 Data Sheet ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
POWER SUPPLY SEQUENCING Table 3.
Simultaneous application of VDD and VSS is necessary to
Parameter Rating
guarantee reliability of the device. In cases where simultaneous V application cannot be guaranteed, VDD must power up before DD to AGND, DGND 0 V to +16.5 V V VSS. When a negative voltage is applied to the analog inputs SS to AGND, DGND 0 V to −16.5 V V before VDD and VSS are ful y powered up, a 560 Ω resistor must DD to AVCC AVCC + 0.7 V to +16.5 V AV be placed on the analog inputs. CC to AGND, DGND −0.3 V to +7 V DVCC to AVCC −0.3 V to AVCC + 0.3 V A number of sequencing combinations can lead to temporary DVCC to DGND, AGND −0.3 V to +7 V high current states; however, when all supplies are powered up, AGND to DGND −0.3 V to +0.3 V the device returns to normal operating currents. The analog VDRIVE to DGND −0.3 V to DVCC + 0.3 V input (AIN) coming before AVCC causes temporary high current Analog Input Voltage to AGND VSS + 1 V to VDD − 1 V on the analog inputs. Digital inputs before DVCC, and DVCC Digital Input Voltage to DGND −0.3 V to VDRIVE + 0.3 V before other supplies, also cause temporary high current states. Digital Output Voltage to DGND −0.3 V to VDRIVE + 0.3 V
THERMAL RESISTANCE
REFIN/REFOUT to AGND −0.3 V to AVCC + 0.3 V Input Current to Any Pin Except Supplies1 ±10 mA θJA is specified for the worst-case conditions, that is, a device Operating Temperature Range −40°C to +85°C soldered in a circuit board for surface-mount packages. These Storage Temperature Range −65°C to +150°C specifications apply to a 4-layer board. Junction Temperature 150°C
Table 4. Thermal Resistance
Pb/Sn Temperature, Soldering
Package Type θJA θJC Unit
Reflow (10 sec to 30 sec) 240(0)°C 64-Lead LQFP 45 11 °C/W Pb-Free Temperature, Soldering Reflow 260(0)°C ESD 1.5 kV
ESD CAUTION
1 Transient currents of up to 100 mA do not cause SCR latch-up. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Rev. 0 | Page 6 of 28 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION PRODUCT HIGHLIGHTS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS POWER SUPPLY SEQUENCING THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION CONVERTER DETAILS Track-and-Hold Amplifiers Analog Input ADC TRANSFER FUNCTION INTERNAL/EXTERNAL REFERENCE TYPICAL CONNECTION DIAGRAM DRIVING THE ANALOG INPUTS INTERFACE OPTIONS Parallel Interface (SER/PAR/SEL = 0) SOFTWARE SELECTION OF ADCS Changing the Analog Input Range (H/S SEL = 0) Changing the Analog Input Range (H/S SEL = 1) Serial Interface (SER/PAR/SEL = 1) SERIAL READ OPERATION DAISY-CHAIN MODE (DCEN = 1, SER/PAR/SEL = 1) Standby/Partial Power-Down Modes of Operation(SER/PAR/SEL = 0 or SER/PAR/SEL = 1) APPLICATION HINTS LAYOUT OUTLINE DIMENSIONS ORDERING GUIDE