el5211a Intersil Corporation, el5211a Datasheet - Page 10

• Manufacturer Part Number: el5211a
• Description: 60mhz Rail-to-rail Input-output Op Amp
• Manufacturer: Intersil Corporation

Output Phase Reversal
The EL5211A is immune to phase reversal as long as the input
voltage is limited from V
a photo of the output of the device with the input voltage driven
beyond the supply rails. Although the device's output will not
change phase, the input's overvoltage should be avoided. If
an input voltage exceeds supply voltage by more than 0.6V,
electrostatic protection diodes placed in the input stage of
the device begin to conduct and overvoltage damage could
occur.
Power Dissipation
With the high-output drive capability of the EL5211A
amplifier, it is possible to exceed the +125°C absolute
maximum junction temperature under certain load current
conditions. Therefore, it is important to calculate the
maximum junction temperature for the application to
determine if load conditions need to be modified for the
amplifier to remain in the safe operating area.
The maximum power dissipation allowed in a package is
determined according to:
P
where:
• T
• T
• Θ
• P
The maximum power dissipation actually produced by an IC
is the total quiescent supply current times the total power
supply voltage, plus the power in the IC due to the loads, or:
P
when sourcing, and:
P
DMAX
DMAX
DMAX
FIGURE 28. OPERATION WITH BEYOND-THE-RAILS INPUT
AMAX
JMAX
DMAX
JA
= Thermal resistance of the package
=
=
=
= Maximum junction temperature
= Maximum ambient temperature
T
-------------------------------------------- -
Σi V
Σi V
= Maximum power dissipation in the package
JMAX
[
[
1V
1V
S
S
Θ
×
×
–
JA
I
I
SMAX
SMAX
T
AMAX
S
- -0.5V to V
+
+
(
(
V
V
S
OUT
10
+ V
–
i V
10µs
–
OUT
S
+ +0.5V. Figure 28 shows
S
- )
i )
×
×
V
T
A
V
I
A
I
S
V
IN
LOAD
LOAD
= +25°C
= ±2.5V
= 1
= 6V
i
P-P
i
]
]
(EQ. 1)
(EQ. 2)
(EQ. 3)
EL5211A
when sinking,
where:
• i = 1 to 2 for dual and 1 to 4 for quad
• V
• I
• V
• I
If we set the two P
can solve for R
and 30 provide a convenient way to see if the device will
overheat. The maximum safe power dissipation can be
found graphically, based on the package type and the
ambient temperature. By using the Equation 3, it is a simple
matter to see if P
curves. To ensure proper operation, it is important to observe
the recommended derating curves shown in Figures 29 and
30.
FIGURE 29. PACKAGE POWER DISSIPATION vs AMBIENT
FIGURE 30. PACKAGE POWER DISSIPATION vs AMBIENT
SMAX
LOAD
S
OUT
= Total supply voltage
i = Maximum output voltage of the application
i = Load current
= Maximum supply current per amplifier
0.6
0.5
0.4
0.3
0.2
0.1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1
0
0
0
JEDEC JESD51-3 LOW EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
JEDEC JESD51-7 HIGH EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
TEMPERATURE
TEMPERATURE
486mW
870mW
LOAD
DMAX
DMAX
25
AMBIENT TEMPERATURE (°C)
25
AMBIENT TEMPERATURE (°C)
i to avoid device overheat. Figures 29
exceeds the device's power derating
equations equal to each other, we
50
50
75
75
85
85
100
100
125
125
April 24, 2007
FN6143.1