ncv8508b ON Semiconductor, ncv8508b Datasheet - Page 14

• Manufacturer Part Number: ncv8508b
• Description: Ncv8508b 5.0 V, 250 Ma Ldo With Watchdog And Reset
• Manufacturer: ON Semiconductor

Calculating Power Dissipation in a Single Output
Linear Regulator
regulator (Figure 25) is:
P D(max) + [V IN(max) * V OUT(min) ] I OUT(max)
where:
permissible value of R
NOTE:
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
ORDERING INFORMATION
Specifications Brochure, BRD8011/D.
NCV85081BPD50R2G
The maximum power dissipation for a single output
V
V
I
application, and
I
I
Once the value of P
OUT(max)
Q
OUT(max)
IN(max)
OUT(min)
is the quiescent current the regulator consumes at
V
Figure 25. Single Output Regulator with Key
IN
Contact factory for other options.
Device
Performance Parameters Labeled
is the maximum input voltage,
.
) V IN(max) I Q
is the minimum output voltage,
is the maximum output current for the
I
IN
R qJA + 150° C *
qJA
REGULATOR
D(max)
}
Output Voltage
can be calculated:
SMART
Control
Features
5.0 V
P D
is known, the maximum
I
Q
T A
I
OUT
Wakeup Rising Delay Time = 12.5 ms
APPLICATION NOTES
Wakeup Period = 25 ms
V
http://onsemi.com
OUT
Delay Time = 3 ms
(R
RESET HIGH to
Timing Option
(1)
(2)
Delay
14
= 60 kΩ)
package section of the data sheet. Those packages with
R
the die temperature below 150°C.
dissipate the heat generated by the IC, and an external
heatsink will be required.
Heatsinks
package to improve the flow of heat away from the IC and
into the surrounding air.
outside environment will have a thermal resistance. Like
series electrical resistances, these resistances are summed to
determine the value of R
where:
R
functions of the package type, heatsink and the interface
between them. These values appear in data sheets of
heatsink manufacturers.
qJA
qJA
The value of R
In some cases, none of the packages will be sufficient to
A heatsink effectively increases the surface area of the
Each material in the heat flow path between the IC and the
R
R
R
R
qJC
qCS
qSA
qJC
s less than the calculated value in Equation 2 will keep
, it too is a function of package type. R
= the junction−to−case thermal resistance,
appears in the package section of the data sheet. Like
= the case−to−heatsink thermal resistance, and
= the heatsink−to−ambient thermal resistance.
R qJA + R qJC ) R qCS ) R qSA
qJA
can then be compared with those in the
SO−8 EP
(Pb−Free)
Package
qJA
:
2500 / Tape & Reel
qCS
Shipping†
and R
qSA
are
(3)