tfa9843aj NXP Semiconductors, tfa9843aj Datasheet - Page 6

• Manufacturer Part Number: tfa9843aj
• Description: Tfa9843aj 20 W Stereo Power Amplifier With Volume Control
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9. Limiting values
10. Thermal characteristics
TFA9843AJ_1
Preliminary data sheet
8.5 Built-in protection circuits
The TFA9843AJ contains two types of temperature sensors; one measures the local
temperatures of the power stages and one measures the global chip temperature. At a
local temperature of the power stage of approximately 185 C or a global temperature of
approximately 150 C this detection circuit switches off the power stages for 2 ms. When
the outputs are switched off the voltage is measured on the outputs. In the event of a
short-circuit to ground or to V
cases the power stages switch-on automatically and the detection will take place again;
however a too high temperature will switch-off the power stages immediately. This can
result in repetitive switching during too high junction temperature. This protects the
TFA9843AJ against short-circuits to ground, to the supply voltage, across the load and too
high chip temperatures.
The protection will only be activated when necessary, so even during a short-circuit
condition, a certain amount of (pulsed) current will still flow through the short-circuit (as
much as the power stage can handle without exceeding the critical temperature level).
Table 6.
In accordance with the Absolute Maximum Rating System (IEC 60134).
Table 7.
Symbol
V
V
I
T
T
P
V
Symbol
R
R
ORM
stg
amb
CC
I
tot
CC(scp)
th(j-a)
th(j-c)
Limiting values
Thermal characteristics
Parameter
supply voltage
input voltage
repetitive peak output current
storage temperature
ambient temperature
total power dissipation
short-circuit protection supply
voltage
Parameter
thermal resistance from
junction to ambient
thermal resistance from
junction to case
Rev. 01 — 28 April 2006
CC
the device will remain in Protection mode. In all other
20 W stereo power amplifier with volume control
Conditions
operating
non-operating
operating
Conditions
in free air
both channels
driven
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
Min
-
-
-
Value
40
2.0
TFA9843AJ
0.3
0.3
55
40
Max
+28
V
4
+150
+85
35
26
CC
+ 0.3
Unit
K/W
K/W
Unit
V
V
A
W
V
6 of 19
C
C