MCP1827 MICROCHIP [Microchip Technology], MCP1827 Datasheet - Page 21

• Manufacturer Part Number: MCP1827
• Description: 1.5A, Low Voltage, Low Quiescent Current LDO Regulator
• Manufacturer: MICROCHIP [Microchip Technology]

5.3.1.2
To estimate the internal junction temperature, the
calculated temperature rise is added to the ambient or
offset temperature. For this example, the worst-case
junction temperature is estimated below:
As you can see from the result, this application will be
operating within the maximum operating junction
temperature of 125°C.
5.3.1.3
From this table you can see the difference in maximum
allowable power dissipation between the TO-220-5
package and the DDPAK-5 package.
© 2006 Microchip Technology Inc.
TO-220-5 (29.3° C/W Rθ
DDPAK-5 (31.2°C/Watt Rθ
P
P
P
P
D(MAX)
D(MAX)
D(MAX)
D(MAX)
T
T
T
J
J
J
Junction Temperature Estimate
Maximum Package Power
Dissipation at 60°C Ambient
Temperature
= T
= 45.12°C + 60.0°C
= 105.12°C
= (125°C – 60°C) / 29.3° C/W
= 2.218W
= (125°C – 60°C)/ 31.2° C/W
= 2.083W
JRISE
+ T
JA
A(MAX)
JA
):
):
MCP1827/MCP1827S
DS22001B-page 21