Page 1
VOLT (Audio Amplifier)
TECHNICAL MANUAL
Page 2
VOLT
Volt is an audio amplifier shield and beneath it has connector that will plug into Piano Hi-FI DAC
and Piano 2.1 Hi-FI DAC. Volt takes the variable output analog audio from the Piano DAC and
through the onboard Texas Instruments TPA3118D2 Class D amplifier delivers audio to the volt
speaker terminals.
The VOLT board requires a 19volt power source to operate. Power should be applied to the
3mm DC JACK. Capacitor Multiplier can be added as a standalone board to VOLT power input.
The Volt is by default muted at power on (mute LED lit). Mute & Shut down state is under
software control.
Top Side Volt Bottom Side Volt
Page 3
Chipset
TPA3118D2
Output
2 x 50W (Max) into a 4 to 8
Class D Operation
90% POWER EFFICIENCY
SNR
102dB
Supply Voltage
UP TO 24V DC
Operating Temperature
-40°C to 85°C Ambient
Board Size
LWH = 58mm * 86.75mm * 32.06mm
Board Weight
120g
VOLT 16 WAY HEADER PIN OUT DETAILS
RPI
SPARKY
SPARKY
RPI
5V
5V
5V
5V
NC
NC
NC
NC
SDA1-I2C
TWI2_SDA
GPIOB14
GPIO4
SCL1-I2C
TWI2_SCK
GPIOB15
GPIO17
NC
NC
GPIOB16
GPIO27
NC
NC
GPIOB30
GPIO24
GPIO23
SDZ_AMP(B31)
MUTE_AMP(B17)
GPIO22
GND
GND
GND
GND
VOLT 8WAY HEADER PIN OUT DETAILS
SIGNAL
SIGNAL
GND
GND
AUDIO RIGHT
AUDIO LEFT
AUDIO RIGHT
AUDIO LEFT
GND
GND
Features and Specifications:
• This class D amplifier goes up to 2 x 50W Max
• The components used are specifically designed for high end audio devices (Würth Inductor,
TI chipset, film capacitors and ± 0.1% thin film resistors)
• VOLT AMP boasts 4 output filters, 4 EMI Snubbers, 4 bootstrap capacitors and gain setting
components
• And Additional Provision for stepped attenuator volume control
-Ω BTL Load
HEADER PIN OUT DETAILS
, 5A
PIN PIN
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
* Highlighted signals only used on VOLT board
PIN PIN
1 2
3 4
5 6
7 8
Page 4
VOLT – Audio Amplifier Board Block Diagram
AM Avoidance Switch Settings
To reduce interference in the AM radio band, theTPA3118D2 has the ability to change the
switching frequency via AM<2:0> pins. We provided switch configuration on VOLT board.
0 = switch towards ON Position, 1 = Switch off position
Default Setting: SW1 – AM2 = ON, AM1 = ON, AM0 = OFF (0, 0, 1)
The US and EU AM bands are similar so you may be able to use the same AM settings for both regions.
Page 5
Sparky + KALI + Piano DAC + Volt
Loading...