STV2246H STMicroelectronics, STV2246H Datasheet - Page 83

• Manufacturer Part Number: STV2246H
• Manufacturer: STMicroelectronics

Specifications of STV2246H

• Lead Free Status / Rohs Status: Compliant

STV224X, STV228X, STV223X - THERMAL CONSIDERATIONS FOR TQFP64 PACKAGE
10 THERMAL CONSIDERATIONS FOR TQFP64 PACKAGE
Proper cooling of the STV223XH circuit (TQFP64 package) requires particular care.
The value of
The circuit is soldered ABOVE a printed circuit board (with as much ground plane as possible) and it ex-
changes freely with its environment by natural convection and radiation.
This 'ideal' condition may not be possible in a real TV set environment and
given value.
In particular, the worst case is when the circuit is soldered BELOW the chassis board in a confined volume
between the chassis board and the bottom of the TV box. In this case,
Recommendations:
■
■
Thermal data given in the data sheet allows an estimation of junction and case temperatures to be made.
For estimation on pin temperature, the following additional data, derived from a measurement on a typical
chassis, can be used:
Example of temperatures ESTIMATION:
(Reminder: only in the case where the circuit is soldered ABOVE the chassis board in a relatively 'free' en-
vironment).
Dissipated power: Pd = 1.3W.
Ambient temperature : Ta = 60°C (inside the TV set).
Junction temperature: Tj = Ta +
Case temperature: Tc = Tj -
Pins temperature: Tp = Tj -
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to perform a quick theoretical temperature evaluation before making the chassis board
later on, to perform detailed temperature measurements on the chassis board, in its real environment
R
thJA
given in the datasheet corresponds to the following condition:
R
thJP
~ 20°C/W;
R
R
thJP
thJC
R
* Pd = 99°C.
thJA
* Pd = 112°C.
* Pd = 125°C.
R
thJA
R
may increase.
thJA
may increase above the