REV. C–4–
AD8007/AD8008
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate
on the human body and test equipment and can discharge without detection. Although the AD8007/
AD8008 features proprietary ESD protection circuitry, permanent damage may occur on devices
subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended
to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
ABSOLUTE MAXIMUM RATINGS*
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6 V
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . See Figure 2
Common-Mode Input Voltage . . . . . . . . . . . . . . . . . . . . . ±V
S
Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . ±1.0 V
Output Short Circuit Duration . . . . . . . . . . . . . . See Figure 2
Storage Temperature . . . . . . . . . . . . . . . . . . –65°C to +125°C
Operating Temperature Range . . . . . . . . . . . –40°C to +85°C
Lead Temperature Range (soldering 10 sec) . . . . . . . . . 300°C
*Stresses above those listed under Absolute Maximum Ratings may cause perma-
nent 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.
MAXIMUM POWER DISSIPATION
The maximum safe power dissipation in the AD8007/AD8008
packages is limited by the associated rise in junction temperature
(T
J
) on the die. The plastic encapsulating the die will locally reach
the junction temperature. At approximately 150°C, which is the
glass transition temperature, the plastic will change its proper-
ties. Even temporarily exceeding this temperature limit may
change the stresses that the package exerts on the die, perma-
nently shifting the parametric performance of the AD8007/
AD8008. Exceeding a junction temperature of 175°C for an
extended period of time can result in changes in the silicon
devices, potentially causing failure.
The still-air thermal properties of the package and PCB (θ
JA
),
ambient temperature (T
A
), and the total power dissipated in the
package (P
D
) determine the junction temperature of the die.
The junction temperature can be calculated as follows:
TT P
ADA
JJ
=+ ×
()
θ
The power dissipated in the package (P
D
) is the sum of the quies-
cent power dissipation and the power dissipated in the package
due to the load drive for all outputs. The quiescent power is the
voltage between the supply pins (V
S
) times the quiescent current
(I
S
). Assuming the load (R
L
) is referenced to midsupply, the
total drive power is V
S
/2 ⫻ I
OUT
, some of which is dissipated in the
package and some in the load (V
OUT
⫻ I
OUT
). The difference
between the total drive power and the load power is the drive
power dissipated in the package.
P
D
= quiescent power + (total drive power – load power):
PVI VV
R
V
R
DSS
S OUT
L
OUT
L
=×
()
+×
−
2
2
RMS output voltages should be considered. If R
L
is referenced
to V
S
, as in single-supply operation, then the total drive power
is V
S
⫻I
OUT
.
If the rms signal levels are indeterminate, then consider the
worst case, when V
OUT
= V
S
/4 for R
L
to midsupply:
PVI
V
R
DSS
S
L
=×
()
+
4
2
In single-supply operation, with R
L
referenced to V
S,
worst case is:
VV
OUT
S
=2
Airflow will increase heat dissipation, effectively reducing θ
JA
.
Also, more metal directly in contact with the package leads from
metal traces, through holes, ground, and power planes will
reduce the θ
JA
. Care must be taken to minimize parasitic capaci-
tances at the input leads of high speed op amps as discussed in
the board layout section.
Figure 2 shows the maximum safe power dissipation in the pack-
age versus the ambient temperature for the SOIC-8 (125°C/
W),
MSOP (150°C/W), and SC70 (210°C/W) packages on a
JEDEC standard 4-layer board. θ
JA
values are approximations.
AMBIENT TEMPERATURE – ⴗC
2.0
1.5
0
–60 100–40
MAXIMUM POWER DISSIPATION – W
–20 0 20 406080
1.0
0.5
SOIC-8
SC70-5
MSOP-8
Figure 2. Maximum Power Dissipation vs.
Temperature for a 4-Layer Board
OUTPUT SHORT CIRCUIT
Shorting the output to ground or drawing excessive current for
the AD8007/AD8008 will likely cause catastrophic failure.