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Customizing the EVM

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3

Customizing the EVM

The TPA6120A2RGY EVM comes in a differential configuration with a gain of 1 V/V. However, the EVM is
designed to be flexible, and can be converted to operate in single-ended inverting and noninverting
configurations. The TPA6120A2RGY EVM can also be operated in a single power supply configuration.

3.1

Single-Ended Inverting Configuration

The TPA6120A2RGY EVM can operate in a single-ended inverting gain configuration without modification.
To operate in single-ended mode with the unmodified EVM, simply put the signal line into the inverting
terminal (–) and the ground line into the noninverting terminal (+). This yields an inverting configuration
with a gain of –1 V/V.

The EVM can also be modified to operate in single-ended inverting only mode with a reduced BOM. To do
this, short resistors R1, R2, R9 (for the left channel) and short R10, R11, and R12 (for the right channel).
Put the signal line on the inverting terminal and the ground line on the noninverting terminal. This yields an
inverting configuration with a gain of –1 V/V.

3.2

Single-Ended Noninverting Configuration

The EVM can operate in a single-ended noninverting gain configuration without modification by applying
the signal line to the noninverting input and the ground line to the inverting input. This yields a gain of +1
V/V.

Another possible setup for noninverting configuration is to remove R9 (for the left channel) and R10 (for
the right channel). Apply the signal line to the noninverting input and the ground line to the inverting input.
This yields a gain of +2 V/V.

3.3

Special Note on Filtering and Capacitors C7 and C8

Capacitors C7 and C8 can be added into the EVM to form a low-pass filter into the amplifier. A typical
application for this is to block out the band noise caused by the output of a DAC. When selecting
capacitance values, the cut-off frequency of the filter becomes 1/(

π

× R × C) instead of 1/(2

π

× R × C)

because the capacitor is connected differentially, which halves the required capacitance.

3.4

Special Note on Gain and Input Configurations

The TPA6120A2RGY high-fidelity audio power amplifier has two separate channels, left and right. It is not
necessary to operate each channel in the same configuration. For test purposes, it may be desirable to
operate the left channel with a noninverting configuration, and the right channel with an inverting
configuration. One channel may be configured to operate with differential inputs while the other channel
with single-ended inputs. The TPA6120A2RGY EVM allows for this flexibility. From a listening standpoint,
the best audio performance is achieved when both channels are operated with the same configuration. In
this case, there is no sound difference between the left and right channels for the human ear to detect.

3.5

Single Power Supply Configuration

The TPA6120A2RGY EVM was not optimized for single power supply operation. To operate in this mode,
the V– terminal must be connected to GND. DC-blocking capacitors must be used at the outputs to
prevent large amounts of dc current from flowing through the headphones due to the high midrail bias.
Likewise, dc-blocking capacitors must be used at the input. R9 and R10 must be removed. The positive
input nodes must be biased to midrail. Resistors R9 and R10 tie the positive node to ground.

4

TPA6120A2RGY Evaluation Module

SLOU394 – July 2014

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Copyright © 2014, Texas Instruments Incorporated

Summary of Contents for TPA6120A2RGY EVM

Page 1: ...rting Configuration 4 3 3 Special Note on Filtering and Capacitors C7 and C8 4 3 4 Special Note on Gain and Input Configurations 4 3 5 Single Power Supply Configuration 4 4 EVM Circuit and Layout 5 4...

Page 2: ...the board 2 Do not short the outputs of the TPA6120A2RGY to either the positive or negative supply when operating with a split power supply When operating with a single power supply do not short the...

Page 3: ...to the RCA jack labeled RIN J6 3 Insert headphones into 3 5 mm headphone jack J4 Power Up 1 Verify correct voltage polarity on the supplies 2 Turn on the power supply 3 Turn on the signal source 4 Ad...

Page 4: ...acitors C7 and C8 Capacitors C7 and C8 can be added into the EVM to form a low pass filter into the amplifier A typical application for this is to block out the band noise caused by the output of a DA...

Page 5: ...e from inputs to minimize stray capacitance 4 2 TPA6120A2RGY EVM PCB Layouts Figure 2 shows the top copper layer of the TPA6120A2RGY EVM The RCA jacks at the inputs are configured to short to ground w...

Page 6: ...ut www ti com Figure 4 TPA6120A2RGY EVM Middle Layer 2 Figure 5 TPA6120A2RGY EVM Bottom Layer 6 TPA6120A2RGY Evaluation Module SLOU394 July 2014 Submit Documentation Feedback Copyright 2014 Texas Inst...

Page 7: ...1uF 25V 10 0603 GRM188R71E104KA01D MuRata C5 X7R 0603 C6 1 10uF CAP CERM 10uF 25V 20 0603 GRM188R61E106MA73 MuRata X5R 0603 H1 H2 H3 4 Bumpon Hemisphere 0 25 X 0 075 75x250 mil SJ5382 3M H4 Clear J1...

Page 8: ...dling and use of EVMs and if applicable compliance in all respects with such laws and regulations 10 User has sole responsibility to ensure the safety of any activities to be conducted by it and its e...

Page 9: ...his equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instruction manual may cause harmful interference to radio communications Opera...

Page 10: ...age et ayant un gain admissible maximal et l imp dance requise pour chaque type d antenne Les types d antenne non inclus dans cette liste ou dont le gain est sup rieur au gain maximal indiqu sont stri...

Page 11: ...sponsible for compliance with all legal regulatory and safety related requirements concerning its products and any use of TI components in its applications notwithstanding any applications related inf...

Page 12: ...401 Building No 5 JiuGe Business Center Lane 2301 Yishan Rd Minhang District Shanghai China Sales Direct 86 21 6401 6692 Email amall ameya360 com QQ 800077892 Skype ameyasales1 ameyasales2 Customer Se...

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