NAU82011WG Datasheet, PDF (10/16 Pages) List of Unclassifed Manufacturers – 2.9 W Mono Filter-Free Class-D Audio Amplifier

6 Special Feature Description
The NAU82011WG offers excellent quantity performance as high efficiency, high output power and low quiescent
current. It also provides the following special features.
6.1 Device Protection
The NAU82011WG includes device protection for three operating scenarios. They are
1. Thermal Overload
2. Short circuit
3. Supply under voltage
6.1.1 Thermal Overload Protection
When the device internal junction temperature reaches 150°C, the NAU82011WG will disable the output drivers. When
the device cools down and a safe operating temperature of 130°C has been reached for at least about 100ms, the output
drivers will be enabled again.
6.1.2 Short Circuit Protection
If a short circuit is detected on any of the pull-up or pull-down devices on the output drivers for at least 16.7µs, the
output drivers will be disabled for 100ms. The output drivers will then be enabled again and check for the short circuit. If
the short circuit is still present, the output drivers are disabled after 16.7µs. This cycle will continue until the short circuit
is removed. The short circuit threshold is 2.0A at 3.6V.
6.1.3 Supply under Voltage Protection
If the supply voltage drops under 2.1V, the output drivers will be disabled while the NAU82011WG control circuitry
still operates. This will avoid the battery supply to drag down too low before the host processor can safely shut down the
devices on the system. If the supply drops further below 1.6 V the internal power on reset is activated and puts the entire
device in power down state.
6.2 Power up and Power down Control
When the supply voltage ramps up, the internal power on reset circuit gets triggered. At this time all internal circuits will
be set to power down state. The device can be enabled by setting the EN pin high. Upon setting the EN pin high, the
device will go through an internal power up sequence in order to minimize ‘pops’ on the speaker output. The complete
power up sequence will take about 4ms. The device will power down in about 30µs, when the EN pin is set low.
It is important to keep the input signal at zero amplitude in order to minimize the ‘pops’ when the EN pin is toggled.
NAU82011WG Datasheet Rev1.0
Page 10 of 16
Dec, 2012