Copyright © 2017, Texas Instruments Incorporated
Copyright © 2017, Texas Instruments Incorporated
Hardware Configuration
14
SLAU754A – January 2018 – Revised August 2019
Copyright © 2018–2019, Texas Instruments Incorporated
TPA3220 Evaluation Module
The Sagami inductor used (7G14J-100M-R) has a saturation current of 18 A. This was selected for the
EVM since the TPA3220 supports a maximum short-circuit output current of 10 A. The inductance versus
current curve for a selected inductor is very important. It is essential for the inductor to maintain at least 5
µH of inductance at the maximum short-circuit current of the power amplifier. The Sagami inductance
versus current curve is available in the 7G14J-100M-R data sheet on the Sagami web site.
Although not required, shielded inductors are used on the EVM as they reduce EMI.
3.8
Reset Circuit and POR
The TPA3220EVM includes RESET supervision so that the TPA3220 device will remain in reset until all
power rails are up and stable. The RESET supervisor also ensures that the device will be put into reset if
one of the power rails experiences a brown out. This circuit, combined with the RESET switch (S1) help
ensure that the TPA3220 can be placed in reset easily, as needed, or automatically if there is a power
supply issue.
illustrates the circuit.
Figure 7. RESET Circuit
3.9
Analog-Input-Board Connector (J28)
The
Analog-Input-Board
(AIB) connector allows for cross compatibility with several
Analog Plug-in
Modules
(APMs) offered by TI. This generic connector provides access to common board connections
such as analog input, analog output, Fault and overtemperature warning (OTW) error reporting, common
board voltages (12 V, 3.3 V, and so forth), and EVM reset. These plug-in modules allow for an application-
specific front end to be plugged into the TPA3220EVM with ease. Examples of plug-in modules include
front ends for guitar amplifier, karaoke, wireless sub-woofer, and front-end audio crossover.
Figure 8. AIB EVM Connector
