TDA8954 NXP Semiconductors, TDA8954 Datasheet - Page 14

• Manufacturer Part Number: TDA8954
• Description: The TDA8954 is a stereo or mono high–efficiency Class D audio power amplifier in asingle IC featuring low power dissipation
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8954_1
Product data sheet
8.4.5 Clock protection (CP)
8.4.6 Overview of protection functions
8.5 Differential audio inputs
The clock signal can be provided by an external oscillator connected to pin OSC (see
Section
be switched off and will remain off until the clock signal has been restored.
An overview of all protection circuits and their respective effects on the output signal is
provided in
Table 5.
[1]
[2]
[3]
[4]
[5]
The audio inputs are fully differential ensuring a high common mode rejection ratio and
maximum flexibility in the application.
Protection
name
TFB
OTP
OCP
WP
UVP
OVP
UBP
CP
•
•
Amplifier gain depends on the junction temperature.
TFB warning signal on pin DIAG1 is activated before TFB is enabled.
The amplifier shuts down completely only if the short-circuit impedance is below the impedance threshold
(Z
Fault condition detected during any Standby-to-Mute transition or during a restart after OCP has been
activated (short-circuit to one of the supply lines).
As soon as the clock is present.
Stereo operation: to avoid supply pumping effects and to minimize peak currents in
the power supply, the output stages should be configured in anti-phase. To avoid
acoustical phase differences, the speakers should also be connected in anti-phase.
Mono BTL operation: the inputs must be connected in anti-parallel. The output of one
channel is inverted and the speaker load is connected between the two outputs of the
TDA8954. In practice (because of the OCP threshold) the maximum output power in
the BTL configuration can be boosted to twice the maximum output power available in
the single-ended configuration.
The input configuration for a mono BTL application is illustrated in
[1]
th
; see
14.4). When this signal is lost, or the clock frequency is too low, the amplifier will
Overview of TDA8954 protection circuits
Section
Table
Complete
shutdown
N
Y
Y
N
Y
Y
Y
Y
[3]
[4]
5.
8.4.2). In all other cases, current limiting results in a clipped output signal.
Rev. 01 — 24 December 2009
Restart
directly
N
N
N
Y
N
N
N
N
[3]
Restart
after
100 ms
N
Y
Y
N
Y
Y
Y
Y
[3]
[5]
PROT pin
active
N
N
Y
N
N
N
N
N
2 × 210 W class-D power amplifier
DIAG1 pin
active
Y
N
N
N
N
N
N
N
[2]
TDA8954
Figure
© NXP B.V. 2009. All rights reserved.
DIAG2 pin
active
N
Y
Y
Y
Y
Y
Y
Y
10.
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