ADA4851-1/ADA4851-2/ADA4851-4
Rev. J | Page 10 of 24
ABSOLUTE MAXIMUM RATINGS
P
D
= Quiescent Power + (Total Drive Power − Load Power)
Table 4.
Parameter Rating
Supply Voltage 12.6 V
Power Dissipation See Figure 5
Common-Mode Input Voltage −V
S
− 0.5 V to +V
S
+ 0.5 V
Differential Input Voltage +V
S
to −V
S
Storage Temperature Range −65°C to +125°C
Operating Temperature Range −40°C to +125°C
Lead Temperature JEDEC J-STD-20
Junction Temperature 150°C
()
L
OUT
L
OUT
S
SS
D
R
V
R
VV
IVP
2
–
2
⎟
⎠
⎞
⎜
⎝
⎛
×+×=
RMS output voltages should be considered. If R
L
is referenced
to −V
S
, as in single-supply operation, the total drive power is
V
S
× I
OUT
. If the rms signal levels are indeterminate, consider the
worst case, when V
OUT
= V
S
/4 for R
L
to midsupply.
()
)
L
S
SS
D
R
V
IVP
2
4/
+×=
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.
In single-supply operation with R
L
referenced to −V
S
, the worst
case is V
OUT
= V
S
/2.
Airflow increases heat dissipation, effectively reducing θ
JA
.
In addition, more metal directly in contact with the package
leads and through holes under the device reduces θ
JA
.
Figure 5 shows the maximum safe power dissipation in the
package vs. the ambient temperature for the 6-lead SOT-23
(170°C/W), the 8-lead MSOP (150°C/W), and the 14-lead
TSSOP (120°C/W) on a JEDEC standard 4-layer board. θ
JA
values are approximations.
THERMAL RESISTANCE
θ
JA
is specified for the worst-case conditions; that is, θ
JA
is specified
for device soldered in circuit board for surface-mount packages.
0
2.0
–55 125
MAXIMUM POWER DISSIPATION (W)
05143-057
AMBIENT TEMPERATURE (°C)
1.5
1.0
0.5
–45–35–25–15–5 5 152535455565758595105115
SOT-23-6
TSSOP
MSOP
Table 5. Thermal Resistance
Package Type θ
JA
Unit
6-lead SOT-23 170 °C/W
8-lead MSOP 150 °C/W
14-lead TSSOP 120 °C/W
Maximum Power Dissipation
The maximum safe power dissipation for the ADA4851-1/
ADA4851-2/ADA4851-4 is limited by the associated rise in
junction temperature (T
J
) on the die. At approximately 150°C,
which is the glass transition temperature, the plastic changes its
properties. 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 junction temperature of 150°C for an
extended period can result in changes in silicon devices,
potentially causing degradation or loss of functionality.
Figure 5. Maximum Power Dissipation vs. Temperature for a 4-Layer Board
ESD CAUTION
The power dissipated in the package (P
D
) is the sum of the
quiescent power dissipation and the power dissipated in the die
due to the drive of the amplifier at the output. The quiescent
power is the voltage between the supply pins (V
S
) times the
quiescent current (I
S
).
