RAK18061 WisBlock Audio Mono Amplifier Module Datasheet

Overview

Description

RAK18061 is a mono amplifier module, part of the WisBlock Audio Series. It is designed based on the TAS2560 from TI, which features an ultra-low-noise audio DAC and Class-D audio amplifier. It incorporates speaker voltage and current sensing feedback for use with speaker protection algorithms.

The RAK18061 can drive the speaker to play audio through the input I2S signals. With other WisBlock modules, it can achieve rich applications, such as recording and voice control functions.

Features

• Module Specifications

  • Audio mono amplifier
  • Amplifier power can be selected by a solder bridge
  • I2S interface for data and I2C interface for control
  • 5.6 W at 1% THD+N into 4-Ω load from 4.2 V supply
  • High-efficiency Class-H boost converter
  • Built-in speaker sense and automatic gain control
  • Thermal, short-circuit, and under-voltage protection

• Module Size

  • 25 x 35 mm

Specifications

Overview

Figure 4129: RAK18061 WisBlock Audio Mono Amplifier Module top and bottom view

Mounting

Mounting to WisBlock Base

Just like other WisBlock modules with a standard WisBlock IO connector, RAK18061 can be mounted to the IO slot of any WisBlock Base board. Figure 2 shows the mounting mechanism of the RAK18061 on a WisBase module, such as the RAK19007.

Figure 4130: RAK18061 mounted to the WisBlock Base

Mounting to WisBlock Audio Stack

With the 3 mm spacer, the RAK18061 can be mounted to the WisBlock Audio Stack. Figure 3 shows the mounting mechanism of the RAK18061 on the WisBlock Audio Stack.

Figure 4131: RAK18061 mounted to the WisBlock Audio Stack

Hardware

The hardware specification is categorized into five (5) parts. It shows the chipset of the module and discusses the pinouts and their corresponding functions and diagrams. It also covers the acoustic, electrical, and mechanical parameters that include the tabular data of the functionalities and standard values of the RAK18061 Audio Mono Amplifier Module.

Chipset

Vendor	Part number
TI	TAS2560

Pin Definition

IO Slot Connector

The RAK18061 WisBlock module comprises a standard IO slot connector. The 40-pin WisBlock IO Slot Connector allows the RAK18061 module to be mounted to a WisBlock baseboard, such as the RAK5005-O. The pin order of the connector and the pinout definition is shown in Figure 4.

Figure 4132: RAK18061 WisIO Connector pinout

NOTE

• 3V3_S and GND are the power supply pins from the WisBlock Base. 3V3_S, VBAT, and VBUS can be selected by the solder bridge as the amplifier power. 3V3_S is always needed for digital power input.
• AMP_INT is a GPIO pin (IO1) from WisBlock Core. Normally, this pin is HIGH. It will be LOW if there is an error within the amplifier.
• Core_I2S_DO, Core_I2S_DI, Core_I2S_WS, and Core_I2S_BCLK are I2S signals.
• Device_I2C_SDA and Device_I2C_SCL are I2C signals, which control the TAS2560.

Stack Connector

The RAK18061 WisBlock module comprises a board-to-board (BTB) connector. The BTB connector allows the RAK18061 module to be stacked with other WisBlock Audio modules, such as the RAK18080 (DSP board) and the RAK18003 (Audio Interposer board). The pin order of the connector and the pinout definition is shown in Figure 5.

Figure 4133: RAK18061 BTB Connector pinout

NOTE

• 3V3, VBAT, VBUS, and GND are power supply pins from the Interposer board. 3V3, VBAT, and VBUS can be selected by the solder bridge as the amplifier power. 3V3 is always needed for digital power input.
• AMP_CTR_IO1 is the GPIO from the interposer board. Normally, this pin is HIGH. This pin will be LOW if there is an error within the amplifier and is shared between both amplifiers.
• AMP_I2S_DO, AMP_I2S_DI, AMP_I2S_WS, and AMP_I2S_BCLK are I2S signals.
• Device_I2C_SDA and Device_I2C_SCL are I2C signals which control the TAS2560. AMP_Check is the GPIO from the interposer board. It is used to check whether an Amplifier board is connected. This pin is LOW when there is no Amplifier board and will be HIGH when an Amplifier board is connected.

Acoustic and Electrical Characteristics

The table below shows the acoustic and electrical characteristics of the RAK18061 AMP Module:

Symbol	Description	Min.	Nom.	Max.	Unit
VBUS	USB or POE supply from WisBase	2.9	5	5.5	V
VBAT	Battery supply from WisBase	3.3	-	4.25	V
3V3_S/3V3	Digital supply voltage	3	3.3	3.6	V
EX_POWER	Extra supply for J12	2.9	5	5.5	V
I1	Boost converter current limit (default)	-	3	-	A
I2	Class-D output current limit	-	4	-	A
RL	Load resistance (Load spec resistance)	3.6	8	-	Ω
THD+N	THD+N @ 1 kHz, Po = 3 W）RL = 8 Ω	-	0.0043	-	%
SNR	Referenced to 1% THD+N at output, A-weighted, RL = 8 Ω	-	110.6	-	dB(A)
Pm	Max output power @ (3 A current limit, THD+N = 1%, 8 Ω load)	-	3.7	-	W
Top	Operating temperature range	-40	-	+85	℃

Mechanical Characteristic

Board Dimensions

Figure 6 shows the dimensions and the mechanical drawing of the RAK18061 module.

Figure 4134: RAK18061 WisBlock AMP Module mechanical drawing

WisConnector PCB Layout

Figure 4135: WisConnector PCB footprint and recommendations

Schematic Diagram

WisBlock Connector, AMP/DSP Board Connector, and Power Select

TAS2560 needs three power supplies. Analog supply voltage and I/O supply voltage are fixed on RAK18061. The amplifier input power supply can be selected via solder bridges (SB1, SB2, SB3, or SB4).

Figure 4136: RAK18061 WisBlock Connector, AMP/DSP Board Connector, and Power Select schematic diagram

The power supply needs to be selected according to the desired speaker output power:

• 3V3 from the WisBlock Base (maximum output current of 750 mA)
• V_BAT from the WisBlock Base (maximum output current of 1 A)
• V_BUS from the WisBlock Base (maximum output current of about 1.25 A)
• EX_Power from an external power supply from J12

NOTE

If you want to achieve a higher speaker output power, use EX_Power.

• Voltage at EX_Power should not exceed 5.5 V.
• Current of EX_Power should be higher than the speaker output power.

Left and Right Channels

Figure 4137: RAK18061 Left and Right Channel Amplifier schematic diagram