Datasheet

AD9508 Data Sheet
Rev. B | Page 10 of 40
ABSOLUTE MAXIMUM RATINGS
Table 10.
Parameter Rating
Supply Voltage (VDD)
3.6 V
Maximum Digital Input Voltage −0.5 V to VDD + 0.5 V
CLK and ACLK
E
−0.5 V to VDD + 0.5 V
Maximum Digital Output Voltage −0.5 V to VDD + 0.5 V
Storage Temperature Range
−65°C to +150°C
Operating Temperature Range
−40°C to +85°C
Lead Temperature (Soldering 10 sec)
300°C
Junction Temperature 150°C
The following equation determines the junction temperature on
the application PCB:
T
J
= T
CASE
+ (Ψ
JT
× P
D
)
where:
T
J
is the junction temperature (°C).
T
CASE
is the case temperature (°C) measured by the customer at
the top center of the package.
Ψ
JT
is the value as indicated in Table 11.
P
D
is the power dissipation.
Values of θ
JA
are provided for package comparison and PCB
design considerations. θ
JA
can be used for a first-order approxi-
mation of T
J
by the following equation:
T
J
= T
A
+ (θ
JA
× P
D
)
where T
A
is the ambient temperature (°C).
Values of θ
JC
are provided for package comparison and PCB
design considerations when an external heat sink is required.
Values of θ
JB
are provided for package comparison and PCB
design considerations.
THERMAL CHARACTERISTICS
Thermal characteristics established using JEDEC51-7 and
JEDEC51-5 2S2P test boards.
Table 11. Thermal Characteristics, 24-Lead LFCSP
Symbol
Thermal Characteristic
(JEDEC51-7 and JEDEC51-5 2S2P
Test Boards
1
)
Value
2
Unit
θ
JA
Junction-to-ambient thermal
resistance per JEDEC JESD51-2 (still
air)
43.5
°C/W
θ
JMA
Junction-to-ambient thermal
resistance, 1.0 m/sec airflow per
JEDEC JESD51-6 (moving air)
40 °C/W
θ
JMA
Junction-to-ambient thermal
resistance, 2.5 m/sec airflow per
JEDEC JESD51-6 (moving air)
38.5 °C/W
θ
JB
Junction-to-board thermal
resistance per JEDEC JESD51-8 (still
air)
16.2 °C/W
θ
JC
Junction-to-case thermal resistance
(die-to-heat sink) per MIL-STD-883,
Method 1012.1
7.1 °C/W
Ψ
JT
Junction-to-top-of-package
characterization parameter per
JEDEC JESD51-2 (still air)
0.33 °C/W
1
The exposed pad on the bottom of the package must be soldered to ground
(VSS) to achieve the specified thermal performance.
2
Results are from simulations. The PCB is a JEDEC multilayer type. Thermal
performance for actual applications requires careful inspection of the
conditions in the application to determine if they are similar to those
assumed in these calculations.
ESD CAUTION
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.