link to page 10 link to page 10 AD7656/AD7657/AD7658Data SheetABSOLUTE MAXIMUM RATINGS TA = 25°C, unless otherwise noted. Table 5. Stresses above those listed under Absolute Maximum Ratings ParameterRating may cause permanent damage to the device. This is a stress V rating only; functional operation of the device at these or any DD to AGND, DGND −0.3 V to +16.5 V other conditions above those indicated in the operational VSS to AGND, DGND +0.3 V to −16.5 V section of this specification is not implied. Exposure to absolute VDD to AVCC AVCC − 0.3 V to 16.5 V maximum rating conditions for extended periods may affect AVCC to AGND, DGND −0.3 V to +7 V device reliability. DVCC to AVCC −0.3 V to AVCC + 0.3 V DVCC to DGND, AGND −0.3 V to +7 V THERMAL RESISTANCE AGND to DGND −0.3 V to +0.3 V θ V JA is specified for the worst-case conditions, that is, a device DRIVE to DGND −0.3 V to DVCC + 0.3 V soldered in a circuit board for surface-mount packages. These Analog Input Voltage to AGND1 VSS − 0.3 V to VDD + 0.3 V specifications apply to a four-layer board. Digital Input Voltage to DGND −0.3 V to VDRIVE + 0.3 V Digital Output Voltage to GND −0.3 V to VDRIVE + 0.3 V Table 6. Thermal Resistance REFIN to AGND −0.3 V to AVCC + 0.3 V Package Typeθ Input Current to Any Pin Except JAθJCUnit Supplies2 ±10 mA 64-Lead LQFP 45 11 °C/W Operating Temperature Range B Version −40°C to +85°C Y Version −40°C to +125°C ESD CAUTION Storage Temperature Range −65°C to +150°C Junction Temperature 150°C Pb/SN Temperature, Soldering Reflow (10 sec to 30 sec) 240(+0)°C Pb-Free Temperature, Soldering Reflow 260(+0)°C 1 If the analog inputs are being driven from alternative VDD and VSS supply circuitry, a 240 Ω series resistor should be placed on the analog inputs. 2 Transient currents of up to 100 mA do not cause SCR latch-up. Rev. D | Page 10 of 32 Document Outline Features Applications Functional Block Diagram General Description Product Highlights Table of Contents Revision History Specifications AD7656 AD7657 AD7658 Timing Specifications Absolute Maximum Ratings Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Terminology Theory of Operation Converter Details Track-and-Hold Section Analog Input Section ADC Transfer Function Reference Section Typical Connection Diagram Driving the Analog Inputs Interface Section Parallel Interface (SER/ = 0) Software Selection of ADCs Changing the Analog Input Range (/S SEL = 0) Changing the Analog Input Range (/S SEL = 1) Serial Interface (SER/ = 1) Serial Read Operation Daisy-Chain Mode (DCEN = 1, SER/ = 1) Standby/Partial Power-Down Modes of Operation Application Hints Layout Power Supply Configuration Outline Dimensions Ordering Guide