el5220t Intersil Corporation, el5220t Datasheet - Page 12

• Manufacturer Part Number: el5220t
• Description: 12mhz Rail-to-rail Input-output Operational Amplifier
• Manufacturer: Intersil Corporation

(typical) the device automatically turns ON the outputs
by putting them in a low impedance (normal)
operating state.
Driving Capacitive Loads
As load capacitance increases, the -3dB bandwidth will
decrease and peaking can occur. Depending on the
application, it may be necessary to reduce peaking and
to improve device stability. To improve device stability,
a snubber circuit or a series resistor may be added to
the output of the EL5220T.
A snubber is a shunt load consisting of a resistor in series
with a capacitor. An optimized snubber can improve the
phase margin and the stability of the EL5220T. The
advantage of a snubber circuit is that it does not draw
any DC load current or reduce the gain.
Another method to reduce peaking is to add a series
output resistor (typically between 1Ω to 10Ω).
Depending on the capacitive loading, a small value
resistor may be the most appropriate choice to
minimize any reduction in gain.
Power Dissipation
With the high-output drive capability of the EL5220T
amplifiers, it is possible to exceed the +150°C absolute
maximum junction temperature under certain load
current conditions. It is important to calculate the
maximum power dissipation of the EL5220T in the
application. Proper load conditions will ensure that the
EL5220T junction temperature stays within a safe
operating region.
The maximum power dissipation allowed in a package is
determined according to Equation 1:
where:
• T
• T
• θ
• P
The total power dissipation produced by an IC is the
total quiescent supply current times the total power
supply voltage, plus the power dissipation in the IC
due to the loads, or:
when sourcing, and:
when sinking, where:
• i = 1 to 2
P
P
P
DMAX
DMAX
DMAX
(1, 2 corresponds to Channel A, B respectively)
JA
JMAX
AMAX
DMAX
= Thermal resistance of the package
=
=
=
= Maximum junction temperature
T
-------------------------------------------- -
Σi V
Σi V
= Maximum ambient temperature
= Maximum power dissipation allowed
JMAX
[
[
S
S
θ
×
×
–
JA
I
I
SMAX
SMAX
T
AMAX
+
+
(
(
V
V
12
S
OUT
+ V
–
i V
–
OUT
S
- ) I
i ) I
×
×
LOAD
LOAD
i
i
]
]
(EQ. 1)
(EQ. 2)
(EQ. 3)
EL5220T
• V
• V
• V
• I
• V
• I
Device overheating can be avoided by calculating the
minimum resistive load condition, R
the highest power dissipation. To find R
two P
V
curves, Figures 32 and 33, for further information.
FIGURE 32. PACKAGE POWER DISSIPATION vs
FIGURE 33. PACKAGE POWER DISSIPATION vs
OUT
(I
SMAX
LOAD
S
S
S
OUT
SMAX
+ = Positive supply voltage
- = Negative supply voltage
2.4
2.0
1.6
1.2
0.8
0.4
0.0
1.0
0.8
0.6
0.4
0.2
0.0
= Total supply voltage (
/I
DMAX
LOAD
0
0
JEDEC JESD51-3 LOW EFFECTIVE
THERMAL CONDUCTIVITY TEST BOARD
= Output voltage
= Load current
= Maximum supply current per amplifier
740mW
2.16W
781mW
595mW
= EL5220T quiescent current ÷ 2)
equations equal to each other and solve for
. Reference the package power dissipation
AMBIENT TEMPERATURE
AMBIENT TEMPERATURE
JEDEC JESD51-7 HIGH EFFECTIVE
THERMAL CONDUCTIVITY TEST BOARD
25
25
AMBIENT TEMPERATURE (°C)
AMBIENT TEMPERATURE (°C)
50
50
75
75
V
DFN8
θ
JA
S
85
+ - V
85
= +160°C/W
MSOP8
DFN8
θ
MSOP8
θ
θ
JA
JA
JA
100
100
LOAD
S
= +58°C/W
-
= +170°C/W
= +210°C/W
)
LOAD
, resulting in
125
125
set the
May 4, 2010
FN6892.0
150
150