NAU8812
Mono Audio Codec with Speaker Driver
1.
GENERAL DESCRIPTION
It is designed for voice
emPowerAudio
™
The NAU8812 is a cost effective and low power wideband MONO audio CODEC.
telephony related applications. Functions include Automatic Level Control (ALC) with noise gate, PGA, standard
audio interface I
2
S, PCM with time slot assignment, and on-chip PLL. The device provides one differential
microphone input and one single ended auxiliary input (multi purpose). There are few variable gain control stages
in the audio path. It also includes MONO line output and integrated BTL speaker driver.
The analog inputs have PGA on the front end, allowing dynamic range optimization with a wide range of input
sources. The microphone amplifiers have a programmable gain from -12dB to +35.25dB to handle both amplified
microphones. In addition to a digital high pass filter to remove DC offset voltages, the ADC also features voice
band digital filtering. Voice-band data is accepted by the audio interface (I
2
S). The DAC converter path includes
filtering and mixing, programmable-gain amplifiers (PGA), and soft muting. The digital interfaces, 2-Wire or SPI,
have independent supply voltage to allow integration into multiple supply systems. The NAU8812 operates at
supply voltages from 2.5V to 3.6V, although the digital core can operate at voltage as low as 1.71V to save power.
The NAU8812 is specified for operation from -40°C to +85°C. AEC-Q100 & TS16949 compliant device is
available upon request.
2.
FEATURES
24-bit signal processing linear Audio CODEC
Audio DAC: 93dB SNR and -84dB THD
Audio ADC: 91dB SNR and -79dB THD
Support variable sample rates from 8 - 48kHz
Integrated BTL Speaker Driver 800mW (8Ω / 5V)
Integrated Headset Driver 40mW (16Ω / 3.3V)
Analog I/O
Integrated programmable Microphone Amplifier
Integrated Line Input and Line Output
Earphone / Speaker / Line Output selection
Microphone / Line Inputs selection
Low Noise bias supplied for microphone
On-chip PLL
Interfaces
I
2
S digital interface PCM time slot assignment
SPI & 2-Wire serial control Interface (I
2
C style; Read/Write capable)
Low Power, Low Voltage
Analog Supply: 2.5V to 3.6V
Digital Supply: 1.71V to 3.6V
Nominal Operating Voltage: 3.3V
Additional features
Programmable ALC
ADC Notch Filter
Programmable High Pass Filter
Digital A/D-D/A Passthrough
AEC-Q100 & TS16949 compliant device available upon request
Industrial temperature: range: –40C to +85C
Applications
VoIP Telephones]
Conference speaker-phone
emPowerAudio
™
Datasheet Revision 2.8
Page 1 of 110
June 2016
NAU8812
3.
PIN DESCRIPTION
Pin Name
VREF
MIC-
MIC+
MICBIAS
NC
VDDA
VSSA
VSSA
VDDL
VDDC
VDDB
VSSD
VSSD
ADCOUT
DACIN
FS
BCLK
MCLK
CSb/GPIO
SCLK
SDIO
SO
MODE
NC
MOUT
SPKOUT+
VSSSPK
VSSSPK
SPKOUT-
VDDSPK
VDDSPK
AUX
28-Pin
1
2
3
4
5
6
7
8
-
9
10
11
-
12
13
14
15
16
17
18
19
-
20
-
21
22
23
24
25
26
27
28
32-Pin
29
30
31
32
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Functionality
Decoupling internal analog mid supply reference
Microphone Negative Input
voltage
Microphone Positive Input
Microphone Bias
No Connect
Analog Supply
Analog Ground
Analog Ground
Logic supply voltage. This pin should not be
connected up to an external supply
Digital Supply Core
Digital Supply Buffer
Digital Ground
Digital Ground
Digital Audio Data Output
Digital Audio Data Input
Frame Sync
Bit Clock
Master Clock
SPI Chip Select or General Purposes 1 I/O
SPI or 2-Wire Serial Clock
SPI Data In or 2-Wire I/O
SPI Data Output
Interface Select (2-Wire or SPI)
No Connect
MONO Output
Speaker Positive Output
Speaker Ground
Speaker Ground
Speaker Negative Output
Speaker Supply
Speaker Supply
Auxiliary Input
A
A
A
A
A
A
A
A
O
O
O
O
O
I
I
I
A
A
A
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
I
O
O
O
I
I
O
O
O
I
I/O
I/O
I
I/O
I
O
O
I
A/D
A
A
A
A
Pin Type
O
I
I
O
Table 1: Pin Description for SSOP and QFN Packages
Notes
1.
2.
3.
4.
The 32-QFN package includes a bulk ground connection pad on the underside of the chip. This bulk ground
should be thermally tied to the PCB, and electrically tied to the analog ground.
Unused analog input pins should be left as no-connection.
Under all condition when digital pins are not used they should be tied to ground.
Pins designated as NC (Not Internally Connected) should be left as no-connection
emPowerAudio
™
Datasheet Revision 2.8
Page 4 of 110
June 2016