Datasheet ADP172 (Analog Devices) - 5

Data Sheet ADP172 ABSOLUTE MAXIMUM RATINGS Table 3.
the application and board layout. In applications where high
Parameter Rating
maximum power dissipation exists, close attention to thermal board design is required. The value of θ VIN to GND −0.3 V to +4.0 V JA may vary, depending on PCB material, layout, and environmental conditions. The VOUT to GND −0.3 V to VIN specified values of θ EN to GND −0.3 V to +4.0 V JA are based on a 4-layer, 4 in. × 3 in. PCB. Refer to JESD51-7 for detailed information regarding board Storage Temperature Range −65°C to +150°C construction. Operating Junction Temperature Range −40°C to +125°C Operating Ambient Temperature Range −40°C to +85°C ΨJB is the junction-to-board thermal characterization parameter Soldering Conditions JEDEC J-STD-020 with units of °C/W. The ΨJB of the package is based on modeling Stresses above those listed under absolute maximum ratings and calculation using a 4-layer board. The Guidelines for Reporting may cause permanent damage to the device. This is a stress and Using Electronic Package Thermal Information: JESD51-12 rating only and functional operation of the device at these or states that thermal characterization parameters are not the same any other conditions above those indicated in the operational as thermal resistances. ΨJB measures the component power flowing section of this specification is not implied. Exposure to absolute through multiple thermal paths rather than a single path as in maximum rating conditions for extended periods may affect thermal resistance, θJB. Therefore, ΨJB thermal paths include device reliability. convection from the top of the package as well as radiation from the package—factors that make ΨJB more useful in real-world
THERMAL DATA
applications. Maximum junction temperature (TJ) is calculated Absolute maximum ratings apply only individually, not in from the board temperature (TB) and power dissipation (PD) combination. The ADP172 can be damaged when the junction using the formula temperature limits are exceeded. Monitoring ambient TJ = TB + (PD × ΨJB) temperature does not guarantee that TJ is within the specified Refer to JESD51-8 and JESD51-12 for more detailed information temperature limits. In applications with high power dissipation about Ψ and poor thermal resistance, the maximum ambient temperature JB. may have to be derated.
THERMAL RESISTANCE
In applications with moderate power dissipation and low PCB θJA and ΨJB are specified for the worst-case conditions, that is, a thermal resistance, the maximum ambient temperature can device soldered in a circuit board for surface-mount packages. exceed the maximum limit as long as the junction temperature
Table 4. Thermal Resistance
is within specification limits. The junction temperature (TJ) of the device is dependent on the ambient temperature (T
Package Type θJA ΨJB Unit
A), the power dissipation of the device (P 4-Ball, 0.5 mm Pitch WLCSP 260 58 °C/W D), and the junction-to- ambient thermal resistance of the package (θ JA).
ESD CAUTION
Maximum junction temperature (TJ) is calculated from the ambient temperature (TA) and power dissipation (PD) using the following formula: TJ = TA + (PD × θJA) Junction-to-ambient thermal resistance (θ JA) of the package is based on modeling and calculation using a 4-layer board. The junction-to-ambient thermal resistance is highly dependent on Rev. E | Page 5 of 20 Document Outline Features Applications Typical Application Circuits General Description Table of Contents Revision History Specifications Input and Output Capacitor, Recommended Specifications Absolute Maximum Ratings Thermal Data Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Applications Information Capacitor Selection Output Capacitor Input Bypass Capacitor Input and Output Capacitor Properties Undervoltage Lockout Enable Feature Current Limit and Thermal Overload Protection Thermal Considerations Printed Circuit Board Layout Considerations Outline Dimensions Ordering Guide