STMicroelectronics TDA7803A, TDA7808 User Manual

UM2758

User manual

Evaluation board for TDA7803A and TDA7808 power amplifiers in PSO package

Introduction

Scope of this document is to describe the EVAL-7803APSO-SA standalone demo module.

It contains the module description, the schematic, the bill of materials and the board layout of the following modules:
6038-469.18 v1.0

In the following chapters it will be referred as 469 module.

UM2758 - Rev 1 - August 2020
For further information contact your local STMicroelectronics sales office.

www.st.com

1 Hardware description

1.1 Board description

This board is based for TDA7803A and TDA7808 in PSO36 package. It is designed to provide 4 x 27 W on 4 Ω
load.

Figure 1. EVAL-7803APSO-SA board Top view

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Hardware description

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Figure 2. EVAL-7803APSO-SA board Bottom view

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Board description

Note: • Demo board are designed with scope to show typical device performance in standard application.

Furthermore, some components mounted on PCB could result downsized for satisfy a full performance
operation. Adequate heat dissipation must be provided for optimal performance: heatsink provided with
demo board ensures optimal dissipation when device is supplied with 14 V supply and a 4 Ω load is
connected to its outputs. For further information about high power measurements please contact ST
application team.

• The Figure 2 is taken without heatsink which is listed in the BOM reported in the Table 1.

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1.2 Connector and connections

Power supply

The power supply, ranging from 4.5 V to 18.5 V, can be connected on J4 screw terminal following the labels.

Outputs

The amplifier outputs are present on J1, J2, J3, J8 screw terminal. The output assigned to each connection is
written nearby the connector

Input control signal

On J5 terminal is possible to find the I2C and I2S inputs. Additional control/monitor signals are available on this
connector: please refer to Section 1.3 Board option.

Board cascading

To test multiple device systems, is possible to connect more than one 469 modules together by means of J6 and
J7. Plugging J6 of one board to J7 of another, the I2C and I2S bus will be shared allowing to control the system by
means of one I2C interface and feed the same audio.

In order to command each device independently from each other, different addresses must be used on each 469
board. The number of 469 modules is limited by the maximum number of address that can be set.

1.3 Board option

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Connector and connections

Address selection

Proper I2C address for 469 module could be set by shorting with a 0 Ω resistor (or tin drop) one resistor from J9 to
J12. Please refer to TDA7901 datasheet for list of available addresses.

3.3 V voltage reference

On board 3.3 V reference (made by R1 and D1) is used for pull-up resistor of digital lines. When accurate current
measurement is needed (i.e. efficiency measurements) voltage reference should be disabled: in this case an
external 3.3v reference must be provided for 3V3 line.

STBY function

Stand by function can be hardware controlled by jumper P1 (3V3 →Device ON or GND → Device standby).

UNMUTE

Hardware unmute function is controlled by P3 (GND → device mute). By default these jumpers are left open
(device internal pull-up). P3 jumper allows also to remote control UNMUTE function through J10 connector (PIN
31, MUTE).

CD/DIAG

CD/DIAG function can be monitored through J10 connector, pin 19.

I2S data line pairing

If only one I2S data line is needed, SDA1 and SDA2 could be shorted through R9 with a 0 Ω (or tin drop).

1.4 Parallelized channels

TDA7803 provides the possibility to parallelize the channels to increase the output current capability. During this
operation one of the two channels in the parallel configuration will become the “Master” channel, the other one will
be the “Slave” channel.

The possible configurations are:

• CH1 and CH2 in parallel: CH1 is the master, CH2 is the slave

• CH3 and CH4 in parallel: CH3 is the master, CH4 is the slave

To use parallel configuration connect the two channels outputs close to the load, respecting output polarities.

Important:
When channels are parallelized, pay attention to the device’s configuration. Play signal with parallelized channels when the
device is configured for single output channels can lead to improper functioning

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