Nuvoton NAU8223 User manual

NAU8223
NAU8223 User Manual July 2012
NAU8223 Evaluation Board User Manual

NAU8223
NAU8223 User Manual July 2012
1. General Description
The NAU8223 is a stereo high efficiency filter-free Class-D audio amplifier, which is capable of
driving a 4Ω load with up to 3W output power. This device provides chip enable pin with
extremely low standby current and fast start-up time. The ability to configure with either
single-ended or differential inputs is included. The NAU8223 has four selectable gain settings of
0dB, 6dB, 12dB, 18dB and 24dB, which can be controlled by a single gain pin. 87dB PSRR,
91% efficiency, ultra low quiescent current (i.e. 2.1mA at 3.7V for 2 channels) and superior EMI
performance the NAU8223 is ideal for the portable applications of battery drive.
2. EVB Set Up

NAU8223
NAU8223 User Manual July 2012
Power Connection
An external DC Voltage supply with a compliance of at least 2 Amperes should be connected to J17 &
J23. The supply leads should be kept short in order to avoid I x R supply voltage drop at the amplifier.
Jumper Settings
Install J25 on Pins 1-2 to turn ON the device, installing it on 2-3 turns the device OFF.
J21 is for Gain setting. J21 open means setting the gain of the device to 0dB.
Installing a jumper in the following pins sets the gain of the device as follows:
5-4: (Center –Right Pin) 6dB
5-3: (Center –Top Pin) 12dB
5-2: (Center -- Left Pin) 18dB
5-1: (Center –Bottom Pin) 24dB.
Input Connection
Jumpers J26 and J27 are for selecting the input configuration mode to either, single ended (install
jumpers) or differential (no jumpers installed).
Output Connection
An 8 ohm 68uH load should be connected on each channel (J3- J7) and (J4 - J8). Connect the outputs
to the inputs of the Audio Precision Analyzer (Balanced) via the AP0025 Aux Filter.
Power Up
For optimum performance the board should be power up with J25 in the power down state. Once the
power is applied J25 can be set to power up the board. Then, the input signal can be applied.
Important note:
When using a power supply, it is recommended to use a 330µF capacitor across the power pins to
suppress any supply glitches, as a safety measure. When a battery is used, the capacitor is
not required. In normal applications too, the capacitor is not required.

NAU8223
NAU8223 User Manual July 2012
3. Schematic: