LT3029 LINER [Linear Technology], LT3029 Datasheet - Page 15

• Manufacturer Part Number: LT3029
• Description: Dual 500mA/500mA Low Dropout, Low Noise, Micropower Linear Regulator
• Manufacturer: LINER [Linear Technology]

Thermal Considerations
The LT3029’s power handling capability limits the maximum
rated junction temperature (125°C, LT3029E/LT3029I/
LT3029MP or 150°C, LT3029H). Two components comprise
the power dissipated by each channel:
Ground pin current is found by examining the GND Pin
Current curves in the Typical Performance Characteristics
section.
Power dissipation for each channel equals the sum of the
two components listed above. Total power dissipation for
the LT3029 equals the sum of the power dissipated by
each channel.
The LT3029’s internal thermal shutdown circuitry protects
both channels of the device if either channel experiences
an overload or fault condition. Activation of the thermal
shutdown circuitry turns both channels off. If the overload
or fault condition is removed, both outputs are allowed
to turn back on. For continuous normal conditions, do
not exceed the maximum junction temperature rating of
125°C (LT3029E/LT3029I/LT3029MP) or 150°C (LT3029H).
Carefully consider all sources of thermal resistance from
junction-to-ambient, including additional heat sources
mounted in proximity to the LT3029. For surface mount
devices, use the heat spreading capabilities of the PC board
and its copper traces to accomplish heat sinking. Copper
APPLICATIONS INFORMATION
1. Output current multiplied by the input/output voltage
2. GND pin current multiplied by the input voltage:
differential: (I
(I
GND
)(V
IN
).
OUT
)(V
IN
– V
OUT
), and
board stiffeners and plated through-holes can also spread
the heat generated by power devices.
The following tables list thermal resistance as a function
of copper area in a fi xed board size. All measurements
were taken in still air on a four-layer FR-4 board with 1oz
solid internal planes, and 2oz external trace planes with a
total board thickness of 1.6mm. For further information
on thermal resistance and using thermal information, refer
to JEDEC standard JESD51, notably JESD51-12.
Table 2. DE Package, 16-Lead DFN
*Device is mounted on topside.
Table 3. MSE Package, 16-Lead MSOP
*Device is mounted on topside.
The junction-to-case thermal resistance (θ
at the Exposed Pad on the back of the die, is 4.3°C/W for
the DFN package, and 5°C/W to 10°C/W for the MSOP
package.
TOPSIDE*
TOPSIDE*
2500mm
1000mm
2500mm
1000mm
225mm
100mm
225mm
100mm
COPPER AREA
COPPER AREA
2
2
2
2
2
2
2
2
BACKSIDE
BACKSIDE
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2
2
2
2
2
2
2
2
BOARD AREA
BOARD AREA
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2500mm
2
2
2
2
2
2
2
2
(JUNCTION-TO-AMBIENT)
(JUNCTION-TO-AMBIENT)
THERMAL RESISTANCE
THERMAL RESISTANCE
JC
36°C/W
37°C/W
38°C/W
40°C/W
35°C/W
36°C/W
37°C/W
39°C/W
LT3029
), measured
15
3029f