Datasheet

TPS61000, TPS61001, TPS61002, TPS61003, TPS61004, TPS61005, TPS61006, TPS61007
SINGLE- AND DUAL-CELL BOOST CONVERTER WITH START-UP INTO FULL LOAD
SLVS279C – MARCH 2000 – REVISED APRIL 2003
20
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
THERMAL INFORMATION
Implementation of integrated circuits in low-profile and fine-pitch surface-mount packages typically requires
special attention to power dissipation. Many system-dependent issues such as thermal coupling, airflow, added
heat sinks and convection surfaces, and the presence of other heat-generating components affect the power-
dissipation limits of a given component.
Three basic approaches for enhancing thermal performance are listed below:
• Improving the power dissipation capability of the PWB design
• Improving the thermal coupling of the component to the PWB
• Introducing airflow in the system
The maximum junction temperature (T
J
) of the TPS6100x devices is 125°C. The thermal resistance of the
10-pin MSOP package (DGS) is R
θJA
= 294°C/W. Specified regulator operation is assured to a maximum
ambient temperature (T
A
) of 85 °C. Therefore, the maximum power dissipation is about 130 mW. More power
can be dissipated if the maximum ambient temperature of the application is lower.
mW
WC
CC
JA
R
A
MAXJ
T
MAXD
P 136
/294
85125)(
)(
=
°
°–°
=
Θ
=
(8)
–
Under normal operating conditions, the sum of all losses generated inside the converter IC is less than 50 mW,
which is well below the maximum allowed power dissipation of 136 mW as calculated in equation 8. Therefore,
power dissipation is given no special attention.
Table 4 shows where the losses inside the converter are generated.
Table 4. Losses Inside the Converter
LOSSES AMOUNTS
Conduction losses in the switch 36 mW
Switching losses 8 mW
Gate drive losses 2.3 mW
Quiescent current losses < 1 mW
TOTAL < 50 mW