Datasheet

Data Sheet ADP2126/ADP2127
Rev. B | Page 5 of 20
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
VIN to GND −0.3 V to +6 V
EXTCLK to GND −0.3 V to +6 V
SW, MODE to GND −0.3 V to VIN
FB to GND −0.3 V to +3.6 V
Operating Ambient Temperature (T
A
) –40°C to +85°C
1
Operating Junction Temperature (T
J
)
at I
LOAD
= 500 mA
–40°C to +125°C
Soldering Conditions JEDEC J-STD-020
1
The maximum operating junction temperature (T
J (MAX)
) supersedes the
maximum operating ambient temperature (T
A (MAX)
). See the Thermal
Considerations section for more information.
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.
Absolute maximum ratings apply individually only, not in
combination.
THERMAL CONSIDERATIONS
The maximum operating junction temperature (T
J (MAX)
)
supersedes the maximum operating ambient temperature
(T
A (MAX)
) because the ADP2126/ADP2127 may be damaged
when the junction temperature limits are exceeded. Monitoring
ambient temperature does not guarantee that T
J
is within the
specified temperature limits.
In applications with high power dissipation and poor PCB
thermal resistance, the maximum ambient temperature may
need to be derated. In applications with moderate power
dissipation and good PCB thermal resistance, the maximum
ambient temperature can exceed the maximum limit as long as
the junction temperature is within specification limits.
The operating junction temperature (T
J
) of the device is dependent
on the ambient temperature (T
A
), the power dissipation of the
device (P
D
), and the junction-to-ambient thermal resistance of
the package (θ
JA
). T
J
is calculated using the following formula:
T
J
= T
A
+ (P
D
× θ
JA
) (1)
See the Applications Information section for further information
on calculating the operating junction temperature for a specific
application.
THERMAL RESISTANCE
θ
JA
of the package is based on modeling and calculation using a
4-layer board. θ
JA
is highly dependent on the application and
board layout. In applications where high maximum power
dissipation exists, attention to thermal board design is required.
The value of θ
JA
may vary, depending on PCB material, layout,
and environmental conditions.
θ
JA
is specified for worst-case conditions, that is, a device soldered
on a circuit board for surface-mount packages. θ
JA
is determined
according to JEDEC Standard JESD51-9 on a 4-layer printed
circuit board (PCB).
Table
3. Thermal Resistance (4-Layer PCB)
Package Type θ
JA
Unit
6-Ball Bumped Bare Die Sales 105 °C/W
6-Pad Embedded Wafer Level Package 105 °C/W
ESD CAUTION