isl28005 Intersil Corporation, isl28005 Datasheet - Page 12

• Manufacturer Part Number: isl28005
• Description: Micropower, Rail-to-rail Input Current Sense Amplifier With Voltage Output
• Manufacturer: Intersil Corporation

Overall Accuracy (V
V
Referred-to-Output (RTO). The output accuracy contains
all offset and gain errors, at a single output voltage.
Equation 2 is used to calculate the % total output
accuracy.
where
V
Example: Gain = 100, For 100mV V
measure 10.1V. The overall accuracy (V
shown in Equation 3.
Power Dissipation
It is possible to exceed the +150°C maximum junction
temperatures under certain load and power supply
conditions. It is therefore important to calculate the
maximum junction temperature (T
applications to determine if power supply voltages, load
conditions, or package type need to be modified to
V
V
OA
OUT
OA
OA
is defined as the total output accuracy
=
=
Actual = V
100
100
+
-
×
×
⎛
⎜
⎝
⎛
⎝
V
------------------------------------------------------------------------------------
10.1 10
----------------------- -
0.1VDC
28VDC
R
OUT
S
C
TO
10
M
( 1mΩ
0.1Ω)
SENSE
–
TO
actual V
V
⎞
⎠
OUT
=
x GAIN
–
1percent
exp
OA
12
R
OUT
P
ected
LOAD
%)
C
exp
D
FIGURE 20. TYPICAL APPLICATION CIRCUIT
ected
JMAX
SENSE
⎞
⎟
⎠
R
R
OA
) for all
S+
S-
) is 1% as
input we
I = 2.86µA
(EQ. 2)
(EQ. 3)
1.35V
ISL28005
gm
gm
LO
HI
remain in the safe operating area. These parameters are
related using Equation 4:
where:
• P
• PD
where:
• T
• θ
• PD
• V
• I
• V
R
T
PD
JMAX
L
dissipation of each amplifier in the package (PD
Equation 5:
amplifier
application
MAX
qMAX
JA
= Load resistance
DMAXTOTAL
MAX
CC
OUTMAX
MAX
MAX
= Thermal resistance of the package
= Total supply voltage
=
=
= Maximum ambient temperature
T
= Maximum quiescent supply current of 1
V
for each amplifier can be calculated using
= Maximum power dissipation of 1 amplifier
MAX
S
= Maximum output voltage swing of the
×
I
+
qMAX
is the sum of the maximum power
θ
-
+
JA
GND
V
xPD
+
CC
(
V
MAXTOTAL
S
- V
OUTMAX
OUT
)
×
2.7VDC
28VDC
V
--------------------------- -
OUTMAX
TO
R
L
February 3, 2010
FN6973.1
(EQ. 4)
(EQ. 5)
MAX
)