CS3511_0912 Datasheet, PDF (15/26 Pages) Cirrus Logic – Stereo 10 W High-efficiency Class-D Audio Power Amplifier

4.6.2
CS3511
Recommended Power-Down Sequence
1. Set the MUTE pin to the logic high state. This will mute the amplifier outputs and hold them in a high-
impedance state.
2. Optionally, the SLEEP pin can now be set to a logic high state to place the device into low power
mode.
3. The power supplies can now be removed.
4.7 Protection Circuits
The CS3511 is protected against under-voltage, over-current, and over-temperature conditions. If one of
these fault conditions are present the amplifier will be muted, the outputs will be tri-stated, and the STATUS
pin will remain in a logic high state until the condition clears. The amplifier will automatically attempt to re-
cover from a detected fault condition.
4.7.1
Under-Voltage Protection
An under-voltage fault occurs if the voltage sensed on the VP terminals, the charge pump, or on V5A
drops below the corresponding falling trigger point seen in the DC Electrical Characteristics table. The
under-voltage fault will automatically clear once the voltage exceeds the associated rising trigger point.
V5GEN, V5A, and V5D must be connected together in order to properly monitor V5D and V5GEN. (See
Figure 1 and Figure 2).
4.7.2
Over-Temperature Protection
An over-temperature fault occurs if the junction temperature of the device exceeds the rising junction ther-
mal error trigger point seen in the AC Electrical Characteristics table. The thermal hysteresis of the device
will cause the fault to automatically clear when the junction temperature drops below the falling junction
thermal error trigger point.
4.7.3
Over-Current Protection
An over-current fault occurs if more current than the over-current error trigger point flows from any of the
amplifier output pins, see AC Electrical Characteristics. Over current can occur if the speaker wires are
shorted together, if one side of the speaker is shorted to ground, or if the speaker impedance is too low.
WARNING: The outputs of the CS3511 should never be shorted to VP. Doing so can result in permanent
damage to the device.
4.8 Integrated 5 V Regulator
The CS3511 includes an internal 5 V regulator in order to provide a supply to the internal digital and analog
circuitry. The output of the regulator is present on the 5VGEN pin. The regulator output pin should have a
bypass capacitor connected to AGND and be connected to the digital and analog supply pins as shown in
the Typical Connection Diagrams in Section 3. The regulator output can be used to set the SLEEP, MUTE,
GAIN0, and GAIN1 pins to a logic high state. The regulator is able to source the maximum current shown
in the DC Electrical Characteristics table.
4.9 Power Dissipation De-Rating
As a result of high-efficiency and good package thermal characteristics, the CS3511 can operate at elevated
ambient temperatures without having to de-rate the output power, assuming 8 Ω output loads or higher. The
exposed pad must be soldered to the PC Board to increase the maximum power dissipation capability
of the CS3511 package. Soldering will minimize the likelihood of an over-temperature fault occurring during
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