TDA7385 STMicroelectronics, TDA7385 Datasheet - Page 11

• Manufacturer Part Number: TDA7385
• Description: IC AMP AUDIO PWR 35W 25FLEXIWATT
• Manufacturer: STMicroelectronics
• Type: Class ABr

Specifications of TDA7385

• Output Type: 4-Channel (Quad)
• Max Output Power X Channels @ Load: 35W x 4 @ 4 Ohm
• Voltage - Supply: 8 V ~ 18 V
• Features: Mute, Short-Circuit and Thermal Protection, Standby
• Mounting Type: Through Hole
• Package / Case: 25-Flexiwatt (bent and staggered leads)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 497-2174-5

TDA7385
3
3.1
3.2
Application hints
Referred to the circuit of
Biasing and SVR
As shown by
GND (pin 16) are internally biased at half supply voltage level (Vs/2), which is derived from
the Supply Voltage Rejection (SVR) block. In this way no current flows through the internal
feedback network. The AC-GND is common to all the 4 amplifiers and represents the
connection point of all the inverting inputs.
Both individual inputs and AC-GND are connected to Vs/2 (SVR) by means of 100 kΩ
resistors.
To ensure proper operation and high supply voltage rejection, it is of fundamental
importance to provide a good impedance matching between Inputs and AC-GROUND
terminations. This implies that C
nominal value and their tolerance should never exceed ± 10 %.
Besides its contribution to the ripple rejection, the SVR capacitor governs the turn ON/OFF
time sequence and, consequently, plays an essential role in the pop optimization during
ON/OFF transients. To conveniently serve both needs, its minimum recommended value
is 10µF.
Figure 14. Input/output biasing.
Input stage
The TDA7385’s inputs are ground-compatible and can stand very high input signals
(± 8 Vpk) without any performances degradation.
If the standard value for the input capacitors (0.1 µF) is adopted, the low frequency cut-off
will amount to 16 Hz.
Figure
V
S
10KΩ
10KΩ
70KΩ
14, all the TDA7385’s main sections, such as Inputs, Outputs AND AC-
Figure
SVR
C1 ÷ C4
3.
0.1μF
1
47μF
100KΩ
100KΩ
, C
C6
2
IN
, C
3
, C
AC_GND
0.1μF
C5
4
, C
5
D95AU302
capacitors have to carry the same
400Ω
400Ω
+
+
-
-
8KΩ
8KΩ
OTHER CHANNELS
TOWARDS
Application hints
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