(PDF) TDA8954TH Datasheet – 2 X 210 W class-D power amplifier
BTL 1 × 420 W, R L = 8 Ω (V DD = 41 V; V SS = − 41 V)
(V = 41 V; V =
SE 2 × 150 W, R = 6 Ω (V = 41 V; V = − 41 V) www.DataSheet.net/
SE 2 × 235 W, R L = 3 Ω (V DD = 39 V; V SS = − 39 V)
SE 2 × 210 W, R L = 4 Ω (V DD = 41 V; V SS = − 41 V)
93 % into a 4
It combines the benefits of Class D efficiency ( ≈ 93 % into a 4 Ω load) with audiophile
load in a stereo Single-Ended (SE) application, or 1
4 Ω load in a stereo Single-Ended (SE) application, or 1 × 420 W into an 8 Ω load in a
The TDA8954 is a stereo or mono high-efficiency Class D audio power amplifier in a
The TDA8954 is a stereo or mono high-efficiency Class D audio power amplifier in a
No Preview Available !
signal from a logic level to a high-power PWM signal switching between the main supply
signal from a logic level to a high-power PWM signal switching between the main supply
NXP Semiconductors
V
PULL-UP
V
DIAG1
T
30
Gain
[dB]
24
0
T
TDA8954
2
×
210 W class-D power amplifier
1 23
010aaa562
(1) Duty cycle of PWM output modulated according to the audio input signal.
(2) Duty cycle of PWM output reduced due to TFB.
(3) Amplifier is switched off due to OTP.
Fig 8. Behavior of TFB, OTP and signal on pin DIAG1
www.DataSheet.net/
8.4.2 OverCurrent Protection (OCP)
In order to guarantee the robustness of the TDA8954, the maximum output current
delivered at the output stages is limited. OCP is built in for each output power switch.
OCP is activated when the current in one of the power transistors exceeds the OCP
threshold (I
ORM
= 12 A) due, for example, to a short-circuit to a supply line or across the
load.
The TDA8954 amplifier distinguishes between low-ohmic short-circuit conditions and
other overcurrent conditions such as a dynamic impedance drop at the loudspeaker. The
impedance threshold (Z
th
) depends on the supply voltage.
How the amplifier reacts to a short circuit depends on the short-circuit impedance:
•
Short-circuit impedance > Z
th
: the amplifier limits the maximum output current to I
ORM
but the amplifier does not shut down the PWM outputs. Effectively, this results in a
clipped output signal across the load (behavior very similar to voltage clipping).
•
Short-circuit impedance < Z
th
: the amplifier limits the maximum output current to I
ORM
and at the same time discharges the capacitor on pin PROT. When C
PROT
is fully
discharged, the amplifier shuts down completely and an internal timer is started.
The value of the protection capacitor (C
PROT
) connected to pin PROT can be between
10 pF and 220 pF (typically 47 pF). While OCP is activated, an internal current source is
enabled that will discharge C
PROT
.
TDA8954_1
Product data sheet
Rev. 01 — 24 December 2009
© NXP B.V. 2009. All rights reserved.
11 of 46
Datasheet pdf – http://www.DataSheet4U.co.kr/
