LM4040
Electrical Characteristics(Notes)
Note 1:
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed
specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test
conditions.
Note 2:
The maximum power dissipation must be derated at elevated temperatures and is dictated by T
Jmax
(maximum junction temperature),
θ
JA
(junction to
ambient thermal resistance), and T
A
(ambient temperature). The maximum allowable power dissipation at any temperature is PD
max
= (T
Jmax
− T
A
)/θ
JA
or the
number given in the Absolute Maximum Ratings, whichever is lower. For the LM4040, T
Jmax
= 125˚C, and the typical thermal resistance (θ
JA
), when board mounted,
is 326˚C/W for the SOT-23 package, and 180˚C/W with 0.4" lead length and 170˚C/W with 0.125" lead length for the TO-92 package and 415˚C/W for the SC70
Package.
Note 3:
The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200 pF capacitor discharged
directly into each pin.
Note 4:
Typicals are at T
J
= 25˚C and represent most likely parametric norm.
Note 5:
Limits are 100% production tested at 25˚C. Limits over temperature are guaranteed through correlation using Statistical Quality Control (SQC) methods.
The limits are used to calculate National’s AOQL.
Note 6:
The boldface (over-temperature) limit for Reverse Breakdown Voltage Tolerance is defined as the room temperature Reverse Breakdown Voltage Tolerance
±
[(∆V
R
/∆T)(max∆T)(V
R
)]. Where,
∆V
R
/∆T is the V
R
temperature coefficient, max∆T is the maximum difference in temperature from the reference point of 25˚C to
T
MIN
or T
MAX
, and V
R
is the reverse breakdown voltage. The total over-temperature tolerance for the different grades in the industrial temperature range where
max∆T = 65˚C is shown below:
A-grade:
±
0.75% =
±
0.1%
±
100 ppm/˚C x 65˚C
B-grade:
±
0.85% =
±
0.2%
±
100 ppm/˚C x 65˚C
C-grade:
±
1.15% =
±
0.5%
±
100 ppm/˚C x 65˚C
D-grade:
±
1.98% =
±
1.0%
±
150 ppm/˚C x 65˚C
E-grade:
±
2.98% =
±
2.0%
±
150 ppm/˚C x 65˚C
The total over-temperature tolerance for the different grades in the exteded temperature range where max
∆T
= 100 ˚C is shown below:
C-grade:
±
1.5% =
±
0.5%
±
100 ppm/˚C x 100˚C
D-grade:
±
2.5% =
±
1.0%
±
150 ppm/˚C x 100˚C
E-grade:
±
3.5% =
±
2.0%
±
150 ppm/˚C x 100˚C
Therefore, as an example, the A-grade LM4040-2.5 has an over-temperature Reverse Breakdown Voltage tolerance of
±
2.5V x 0.75% =
±
19 mV.
Note 7:
Load regulation is measured on pulse basis from no load to the specified load current. Output changes due to die temperature change must be taken into
account separately.
Note 8:
Thermal hysteresis is defined as the difference in voltage measured at +25˚C after cycling to temperature -40˚C and the 25˚C measurement after cycling
to temperature +125˚C.
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