TDA8941P Datasheet, PDF (15/21 Pages) NXP Semiconductors – 1.5 W mono Bridge Tied Load BTL audio amplifier

Philips Semiconductors
TDA8941P
1.5 W mono BTL audio amplifier
14.2 Thermal behaviour and T_amb(max) calculation
The measured maximum thermal resistance of the IC package, R_th(j-a) is 100 K/W.
A calculation for the maximum ambient temperature can be made, with the following
parameters:
V_CC = 9 V and R_L = 16 Ω
T_j(max) = 150 °C.
R_th(tot) is the total thermal resistance between the junction and the ambient.
At V_CC = 9 V and R_L = 16 Ω the measured worst-case sine-wave dissipation is
1.15 W; see Figure 11. For T_j(max) = 150 °C the maximum ambient temperature is:
T_amb(max) = 150 – 1.15 × 100 = 35 °C
The calculation above is for an application at worst-case (stereo) sine-wave output
signals. In practice music signals will be applied, which decreases the maximum
power dissipation to approximately half of the sine-wave power dissipation (see
Section 8.2.2). For T_j(max) = 150 °C the maximum ambient temperature is:
T_amb(max) = 150 – 0.6 × 100 = 90 °C
To increase the lifetime of the IC, T_j(max) should be reduced to 125 °C. This results in:
T_amb(max) = 125 – 0.6 × 100 = 65 °C
15. Test information
15.1 Quality information
The General Quality Specification for Integrated Circuits, SNW-FQ-611D is
applicable.
15.2 Test conditions
T_amb = 25 °C; V_CC = 9 V; f = 1 kHz; R_L = 16 Ω; audio pass band 22 Hz to 22 kHz;
unless otherwise specified.
Remark: In the graphs as function of frequency no bandpass filter was applied;
see Figure 7 and 12.
9397 750 06864
Product specification
Rev. 02 — 7 April 2000
© Philips Electronics N.V. 2000. All rights reserved.
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