Datasheet AD9257-EP (Analog Devices) - 9

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Data Sheet AD9257-EP ABSOLUTE MAXIMUM RATINGS THERMAL CHARACTERISTICS Table 6.
The exposed pad must be soldered to the ground plane for the
Parameter Rating
LFCSP package. Soldering the exposed pad to the PCB increases Electrical the reliability of the solder joints and maximizes the thermal AVDD to AGND −0.3 V to +2.0 V capability of the package. DRVDD to AGND −0.3 V to +2.0 V Digital Outputs (D± x, DCO+, DCO−, FCO+, −0.3 V to +2.0 V
Table 7. Thermal Resistance
FCO−) to AGND
Airflow
CLK+, CLK− to AGND −0.3 V to +2.0 V
Velocity Package Type (m/sec) θ 1, 2 θ 1, 3 θ 1, 4

1, 2 Unit
VIN+ x, VIN− x to AGND −0.3 V to +2.0 V
JA JC JB JT
64-Lead LFCSP 0 22.3 1.4 N/A 0.1 °C/W SCLK/DTP, SDIO/DFS, CSB to AGND −0.3 V to +2.0 V 9 mm × 9 mm 1.0 19.5 N/A 11.8 0.2 °C/W SYNC, PDWN to AGND −0.3 V to +2.0 V (CP-64-4) 2.5 17.5 N/A N/A 0.2 °C/W RBIAS, VCM to AGND −0.3 V to +2.0 V 1 Per JEDEC 51-7, plus JEDEC 25-5 2S2P test board. VREF, SENSE to AGND −0.3 V to +2.0 V 2 Per JEDEC JESD51-2 (still air) or JEDEC JESD51-6 (moving air). Environmental 3 Per MIL-Std 883, Method 1012.1. 4 Operating Temperature Range (Ambient) −55°C to +125°C Per JEDEC JESD51-8 (still air). Maximum Junction Temperature 150°C Typical θJA is specified for a 4-layer PCB with a solid ground Lead Temperature (Soldering, 10 sec) 300°C plane. As shown Table 7, airflow improves heat dissipation, Storage Temperature Range (Ambient) −65°C to +150°C which reduces θJA. In addition, metal in direct contact with the Stresses at or above those listed under Absolute Maximum package leads from metal traces, through holes, ground, and Ratings may cause permanent damage to the product. This is a power planes reduces θJA. stress rating only; functional operation of the product at these or any other conditions above those indicated in the operational
ESD CAUTION
section of this specification is not implied. Operation beyond the maximum operating conditions for extended periods may affect product reliability. Rev. A | Page 9 of 13 Document Outline FEATURES ENHANCED PRODUCT FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS DC SPECIFICATIONS AC SPECIFICATIONS DIGITAL SPECIFICATIONS SWITCHING SPECIFICATIONS TIMING SPECIFICATIONS Timing Diagrams ABSOLUTE MAXIMUM RATINGS THERMAL CHARACTERISTICS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS OUTLINE DIMENSIONS ORDERING GUIDE