Datasheet

AD8278/AD8279
Rev. C | Page 7 of 24
ABSOLUTE MAXIMUM RATINGS
Table 6.
Parameter Rating
Supply Voltage ±18 V
Maximum Voltage at Any Input Pin −V
S
+ 40 V
Minimum Voltage at Any Input Pin +V
S
− 40 V
Storage Temperature Range −65°C to +150°C
Specified Temperature Range −40°C to +85°C
Package Glass Transition Temperature (T
G
) 150°C
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.
THERMAL RESISTANCE
The θ
JA
values in Table 7 assume a 4-layer JEDEC standard
board with zero airflow.
Table 7. Thermal Resistance
Package Type θ
JA
Unit
8-Lead MSOP 135 °C/W
8-Lead SOIC 121 °C/W
14-Lead SOIC 105 °C/W
MAXIMUM POWER DISSIPATION
The maximum safe power dissipation for the AD8278 and
AD8279 are limited by the associated rise in junction tempera-
ture (T
J
) on the die. At approximately 150°C, which is the glass
transition temperature, the properties of the plastic change.
Even temporarily exceeding this temperature limit may change
the stresses that the package exerts on the die, permanently shifting
the parametric performance of the amplifiers. Exceeding a
temperature of 150°C for an extended period may result in a
loss of functionality.
2.0
1.6
1.2
0.8
0.4
0
–50 0–25 255075100125
MAXIMUM POWER DISSIPATION (W)
AMBIENT TEMERATURE (°C)
T
J
MAX = 150°C
MSOP

JA
= 135°C/W
SOIC

JA
= 121°C/W
08308-002
Figure 3. Maximum Power Dissipation vs. Ambient Temperature
SHORT-CIRCUIT CURRENT
The AD8278 and AD8279 have built-in, short-circuit protection
that limits the output current (see Figure 29 for more information).
While the short-circuit condition itself does not damage the
part, the heat generated by the condition can cause the part to
exceed its maximum junction temperature, with corresponding
negative effects on reliability. Figure 3 and Figure 29, combined
with knowledge of the supply voltages and ambient temperature of
the part, can be used to determine whether a short circuit will
cause the part to exceed its maximum junction temperature.
ESD CAUTION