SLASEG8A March 2016 – July 2017 TAS5782M
PRODUCTION DATA.
NOTE
Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.
This section details the information required to configure the device for several popular configurations and provides guidance on integrating the TAS5782M device into the larger system.
The Supporting Component Requirements table in each application description section lists the details of the supporting required components in each of the System Application Schematics.
Where possible, the supporting component requirements have been consolidated to minimize the number of unique components which are used in the design. Component list consolidation is a method to reduce the number of unique part numbers in a design, to ease inventory management, and to reduce the manufacturing steps during board assembly. For this reason, some capacitors are specified at a higher voltage than what would normally be required. An example of this is a 50-V capacitor may be used for decoupling of a 3.3-V power supply net.
In this example, a higher voltage capacitor can be used even on the lower voltage net to consolidate all caps of that value into a single component type. Similarly, several unique resistors that have all the same size and value but different power ratings can be consolidated by using the highest rated power resistor for each instance of that resistor value.
While this consolidation can seem excessive, the benefits of having fewer components in the design can far outweigh the trivial cost of a higher voltage capacitor. If lower voltage capacitors are already available elsewhere in the design, they can be used instead of the higher voltage capacitors. In all situations, the voltage rating of the capacitors must be at least 1.45 times the voltage of the voltage which appears across them. The power rating of the capacitors should be 1.5 times to 1.75 times the power dissipated in it during normal use case.
Because the layout is important to the overall performance of the circuit, the package size of the components shown in the component list was intentionally chosen to allow for proper board layout, component placement, and trace routing. In some cases, traces are passed in between two surface mount pads or ground plane extensions from the TAS5782M device and into to the surrounding copper for increased heat-sinking of the device. While components may be offered in smaller or larger package sizes, it is highly recommended that the package size remain identical to the size used in the application circuit as shown. This consistency ensures that the layout and routing can be matched very closely, which optimizes thermal, electromagnetic, and audio performance of the TAS5782M device in circuit in the final system.
The TAS5782M device is often used with a low-pass filter, which is used to filter out the carrier frequency of the PWM modulated output. This filter is frequently referred to as the L-C Filter, due to the presence of an inductive element L and a capacitive element C to make up the 2-pole filter.
The L-C filter removes the carrier frequency, reducing electromagnetic emissions and smoothing the current waveform which is drawn from the power supply. The presence and size of the L-C filter is determined by several system level constraints. In some low-power use cases that have no other circuits which are sensitive to EMI, a simple ferrite bead or a ferrite bead plus a capacitor can replace the traditional large inductor and capacitor that are commonly used. In other high-power applications, large toroid inductors are required for maximum power and film capacitors can be used due to audio characteristics. Refer to the application report Class-D LC Filter Design (SLOA119) for a detailed description on the proper component selection and design of an L-C filter based upon the desired load and response.
The TAS5782M device includes an I2C compatible control port to configure the internal registers of the TAS5782M device. The control console software provided by TI is required to configure the device. More details regarding programming steps, and a few important notes are available below and also in the design examples that follow.
The TAS5782M device has several methods by which the device can reset the register, interpolation filters, and DAC modules. The registers offer the flexibility to do these in or out of shutdown as well as in or out of standby. However, there can be issues if the reset bits are toggled in certain illegal operation modes.
Any of the following routines can be used with no issue:
Two reset routines are not supported and should be avoided. If used, they can cause the device to become unresponsive. These unsupported routines are shown below.
For the stereo (BTL) PCB layout, see Figure 85.
A 2.0 system refers to a system in which there are two full range speakers without a separate amplifier path for the speakers which reproduce the low-frequency content. In this system, two channels are presented to the amplifier via the digital input signal. These two channels are amplified and then sent to two separate speakers. In some cases, the amplified signal is further separated based upon frequency by a passive crossover network after the L-C filter. Even so, the application is considered 2.0.
Most commonly, the two channels are a pair of signals called a stereo pair, with one channel containing the audio for the left channel and the other channel containing the audio for the right channel. While certainly the two channels can contain any two audio channels, such as two surround channels of a multi-channel speaker system, the most popular occurrence in two channels systems is a stereo pair.
Figure 80 shows the 2.0 (Stereo BTL) system application.
The requirements for the supporting components for the TAS5782M device in a Stereo 2.0 (BTL) system is provided in Table 21.
REFERENCE DESIGNATOR |
VALUE | SIZE | DETAILED DESCRIPTION |
---|---|---|---|
U100 | TAS5782M | 48 Pin TSSOP | Digital-input, closed-loop class-D amplifier |
R100 | See the Adjustable Amplifier Gain and Switching Frequency Selection section | 0402 | 1%, 0.063 W |
R101 | 0402 | 1%, 0.063 W | |
L100, L101, L102, L103 | See the Amplifier Output Filtering section | ||
C100, C121 | 0.1 µF | 0402 | Ceramic, 0.1 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C104, C108, C111, C115 | 0.22 µF | 0603 | Ceramic, 0.22 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C109, C110, C116, C117 | 0.68 µF | 0805 | Ceramic, 0.68 µF, ±10%, X7R Voltage rating must be > 1.8 × VPVDD |
C103 | 1 µF | 0603 (this body size chosen to aid in trace routing) |
Ceramic, 1 µF, ±10%, X7R Voltage rating must be > 16 V |
C105, C118, C119, C120 | 1 µF | 0402 | Ceramic, 1 µF, 6.3V, ±10%, X5R |
C106, C107, C113, C114 | 2.2 µF | 0402 | Ceramic, 2.2 µF, ±10%, X5R At a minimum, voltage rating must be > 10V, however higher voltage caps have been shown to have better stability under DC bias. Refer to the guidance provided in the TAS5782M for suggested values. |
C101, C102, C122, C123 | 22 µF | 0805 | Ceramic, 22 µF, ±20%, X5R Voltage rating must be > 1.45 × VPVDD |
Table 22 shows the application specific performance plots for Stereo 2.0 (BTL) systems.
PLOT TITLE | FIGURE NUMBER |
---|---|
Output Power vs PVDD | Figure 23 |
THD+N vs Frequency, VPVDD = 12 V | Figure 24 |
THD+N vs Frequency, VPVDD = 15 V | Figure 25 |
THD+N vs Frequency, VPVDD = 18 V | Figure 26 |
THD+N vs Frequency, VPVDD = 24 V | Figure 27 |
THD+N vs Power, VPVDD = 12 V | Figure 28 |
THD+N vs Power, VPVDD = 15 V | Figure 29 |
THD+N vs Power, VPVDD = 18 V | Figure 30 |
THD+N vs Power, VPVDD = 24 V | Figure 31 |
Idle Channel Noise vs PVDD | Figure 32 |
Efficiency vs Output Power | Figure 33 |
DVDD PSRR vs. Frequency | Figure 39 |
AVDD PSRR vs. Frequency | Figure 40 |
CPVDD PSRR vs. Frequency | Figure 41 |
For the mono (PBTL) PCB layout, see Figure 87.
A mono system refers to a system in which the amplifier is used to drive a single loudspeaker. Parallel Bridge Tied Load (PBTL) indicates that the two full-bridge channels of the device are placed in parallel and drive the loudspeaker simultaneously using an identical audio signal. The primary benefit of operating the TAS5782M device in PBTL operation is to reduce the power dissipation and increase the current sourcing capabilities of the amplifier output. In this mode of operation, the current limit of the audio amplifier is approximately doubled while the on-resistance is approximately halved.
The loudspeaker can be a full-range transducer or one that only reproduces the low-frequency content of an audio signal, as in the case of a powered subwoofer. Often in this use case, two stereo signals are mixed together and sent through a low-pass filter to create a single audio signal which contains the low frequency information of the two channels. Conversely, advanced digital signal processing can create a low-frequency signal for a multichannel system, with audio processing which is specifically targeted on low-frequency effects.
Because low-frequency signals are not perceived as having a direction (at least to the extent of high-frequency signals) it is common to reproduce the low-frequency content of a stereo signal that is sent to two separate channels. This configuration pairs one device in Mono PBTL configuration and another device in Stereo BTL configuration in a single system called a 2.1 system. The Mono PBTL configuration is detailed in the 2.1 (Stereo BTL + External Mono Amplifier) Systems section. shows the Mono (PBTL) system application
The requirements for the supporting components for the TAS5782M device in a Mono (PBTL) system is provided in Table 23.
REFERENCE DESIGNATOR |
VALUE | SIZE | DETAILED DESCRIPTION |
---|---|---|---|
U200 | TAS5782M | 48 Pin TSSOP | Digital-input, closed-loop class-D amplifier with 96kHz processing |
R200 | See the Adjustable Amplifier Gain and Switching Frequency Selection section | 0402 | 1%, 0.063 W |
R201 | 0402 | 1%, 0.063 W | |
R202 | 0402 | 1%, 0.063 W | |
L200, L201 | See theAmplifier Output Filtering section | ||
C216, C201 | 0.1 µF | 0402 | Ceramic, 0.1 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C208, C209, C214, C215 | 0.22 µF | 0603 | Ceramic, 0.22 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C220, C221 | 0.68 µF | 0805 | Ceramic, 0.68 µF, ±10%, X7R Voltage rating must be > 1.8 × VPVDD |
C200 | 1 µF | 0603 (this body size chosen to aid in trace routing) |
Ceramic, 1 µF, ±10%, X7R Voltage rating must be > 16 V |
C205, C211, C213, C212 | 1 µF | 0402 | Ceramic, 1 µF, 6.3 V, ±10%, X5R |
C202, C217, C352, C367 | 1 µF | 0805 (this body size chosen to aid in trace routing) |
Ceramic, 1 µF, ±10%, X5R Voltage rating must be > 1.45 × VPVDD |
C206, C207 | 2.2 µF | 0402 | Ceramic, 2.2 µF, ±10%, X5R At a minimum, voltage rating must be > 10V, however higher voltage caps have been shown to have better stability under DC bias please follow the guidance provided in the TAS5782M for suggested values. |
C203, C218 | 22 µF | 0805 | Ceramic, 22 µF, ±20%, X5R Voltage rating must be > 1.45 × VPVDD |
C204, C219 | 390 µF | 10 × 10 | Aluminum, 390 µF, ±20%, 0.08-Ω Voltage rating must be > 1.45 × VPVDD Anticipating that this application circuit would be followed for higher power subwoofer applications, these capacitors are added to provide local current sources for low-frequency content. These capacitors can be reduced or even removed based upon final system testing, including critical listening tests when evaluating low-frequency designs. |
Table 24 shows the application specific performance plots for Mono (PBTL) Systems
PLOT TITLE | FIGURE NUMBER |
---|---|
Output Power vs PVDD | Figure 47 |
THD+N vs Frequency, VPVDD = 12 V | Figure 48 |
THD+N vs Frequency, VPVDD = 15 V | Figure 49 |
THD+N vs Frequency, VPVDD = 18 V | Figure 50 |
THD+N vs Frequency, VPVDD = 24 V | Figure 51 |
THD+N vs Power, VPVDD = 12 V | Figure 52 |
THD+N vs Power, VPVDD = 15 V | Figure 53 |
THD+N vs Power, VPVDD = 18 V | Figure 54 |
THD+N vs Power, VPVDD = 24 V | Figure 55 |
Idle Channel Noise vs PVDD | Figure 56 |
Efficiency vs Output Power | Figure 57 |
Figure 89 shows the PCB Layout for the 2.1 System.
To increase the low-frequency output capabilities of an audio system, a single subwoofer can be added to the system. Because the spatial clues for audio are predominately higher frequency than that reproduced by the subwoofer, often a single subwoofer can be used to reproduce the low frequency content of several other channels in the system. This is frequently referred to as a dot one system. A stereo system with a subwoofer is referred to as a 2.1 (two-dot-one), a 3 channel system with subwoofer is referred to as a 3.1 (three-dot-one), a popular surround system with five speakers and one subwoofer is referred to as a 5.1, and so on.
In higher performance systems, the subwoofer output can be enhanced using digital audio processing as was done in the high-frequency channels. To accomplish this, two TAS5782M devices are used — one for the high frequency left and right speakers and one for the mono subwoofer speaker. In this system, the audio signal can be sent from the TAS5782M device through the SDOUT pin. Alternatively, the subwoofer amplifier can accept the same digital input as the stereo, which might come from a central systems processor. Figure 82 shows the 2.1 (Stereo BTL + External Mono Amplifier) system application.
The requirements for the supporting components for the TAS5782M device in a 2.1 (Stereo BTL + External Mono Amplifier) system is provided in Table 25.
REFERENCE DESIGNATOR |
VALUE | SIZE | DETAILED DESCRIPTION |
---|---|---|---|
U300 | TAS5782M | 48 Pin TSSOP | Digital-input, closed-loop class-D amplifier 96kHz Processing |
R300, R350 | See the Adjustable Amplifier Gain and Switching Frequency Selection section | 0402 | 1%, 0.063 W |
R301, R351 | 0402 | 1%, 0.063 W | |
R352 | 0402 | 1%, 0.063 W | |
L300, L301, L302, L303 | See the Amplifier Output Filtering section | ||
L350, L351 | |||
C394, C395, C396, C397, C398, C399 | 0.01 µF | 0603 | Ceramic, 0.01 µF, 50 V, +/-10%, X7R |
C300, C321, C351, C366 | 0.1 µF | 0402 | Ceramic, 0.1 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C304, C308, C311, C315, C358, C359, C364, C365 | 0.22 µF | 0603 | Ceramic, 0.22 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C309, C310, C316, C317, C370, C371 | 0.68 µF | 0805 | Ceramic, 0.68 µF, ±10%, X7R Voltage rating must be > 1.8 × VPVDD |
C303, C350, C312, C360 | 1 µF | 0603 | Ceramic, 1 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C305, C318, C319, C320, C355, C361, C363, C312, C362 | 1 µF | 0402 | Ceramic, 1 µF, 6.3V, ±10%, X5R |
C352, C367 | 1 µF | 0805 | Ceramic, 1 µF, ±10%, X7R Voltage rating must be > 1.45 × VPVDD |
C306, C307, C313, C314, C356, C357, | 2.2 µF | 0402 | Ceramic, 2.2 µF, ±10%, X5R Voltage rating must be > 1.45 × VPVDD |
C301, C302, C322, C323, C353, C368 | 22 µF | 0805 | Ceramic, 22 µF, ±20%, X5R Voltage rating must be > 1.45 × VPVDD |
C354, C369 | 390 µF | 10 × 10 | Aluminum, 390 µF, ±20%, 0.08 Ω Voltage rating must be > 1.45 × VPVDD |
Table 26 shows the application specific performance plots for 2.1 (Stereo BTL + External Mono Amplifier) Systems
DEVICE | PLOT TITLE | FIGURE NUMBER |
---|---|---|
U300 | Output Power vs PVDD | Figure 23 |
THD+N vs Frequency, VPVDD = 12 V | Figure 24 | |
THD+N vs Frequency, VPVDD = 15 V | Figure 25 | |
THD+N vs Frequency, VPVDD = 18 V | Figure 26 | |
THD+N vs Frequency, VPVDD = 24 V | Figure 27 | |
THD+N vs Power, VPVDD = 12 V | Figure 28 | |
THD+N vs Power, VPVDD = 15 V | Figure 29 | |
THD+N vs Power, VPVDD = 18 V | Figure 30 | |
THD+N vs Power, VPVDD = 24 V | Figure 31 | |
Idle Channel Noise vs PVDD | Figure 32 | |
Efficiency vs Output Power | Figure 33 | |
U301 | PVDD PSRR vs Frequency | Figure 38 |
Output Power vs PVDD | Figure 47 | |
THD+N vs Frequency, VPVDD = 12 V | Figure 48 | |
THD+N vs Frequency, VPVDD = 15 V | Figure 49 | |
THD+N vs Frequency, VPVDD = 18 V | Figure 50 | |
THD+N vs Frequency, VPVDD = 24 V | Figure 51 | |
THD+N vs Power, VPVDD = 12 V | Figure 52 | |
THD+N vs Power, VPVDD = 15 V | Figure 53 | |
THD+N vs Power, VPVDD = 18 V | Figure 54 | |
THD+N vs Power, VPVDD = 24 V | Figure 55 | |
Idle Channel Noise vs PVDD | Figure 56 | |
Efficiency vs Output Power | Figure 57 | |
U300 and U301 |
DVDD PSRR vs. Frequency | Figure 39 |
AVDD PSRR vs. Frequency | Figure 40 | |
CPVDD PSRR vs. Frequency | Figure 41 | |
Powerdown Current Draw vs. PVDD | Figure 47 |