TPA3255: THD+N of TPA3255 from datasheet

user5327551

Part Number: TPA3255

I would like to know if the THD+N from the datasheet of TPA3255 was taken from EVM or with a direct connection to the XLR inputs (so bypassing the front end/opamp of the EVM)

over 5 years ago

0 Caro Walter over 5 years ago

TI__Mastermind 22172 points

Hello user,

The THD+N measurements are taken on the EVM with these conditions:

All Measurements taken at audio frequency = 1 kHz, PVDD_X = 51V, GVDD_X = 12 V, RL = 2Ω, fS = 450 kHz, ROC = 22 kΩ, TC = 75°C, Output Filter: LDEM = 10μH, CDEM = 1 µF, MODE = 10, AES17 + AUX-0025 measurement filters, unless otherwise noted.

Most audio analyzers will not give correct readings of Class-D amplifiers’ performance due to their sensitivity to out of band noise present at the amplifier output. AES-17 + AUX-0025 pre-analyzer filters are recommended to use for Class-D amplifier measurements. In absence of such filters, a 30-kHz low-pass filter (10 Ω + 47 nF) can be used to reduce the out of band noise remaining on the amplifier outputs.

All the best,

Carolina

0 user5327551 over 5 years ago in reply to Caro Walter

Intellectual 830 points

Ok but the signal was feed direct to TPA32xx or did it pass through the opamps

0 Robert Clifton56 over 5 years ago in reply to user5327551

TI__Mastermind 27500 points

Hi user5327551,

We don't use the EVM for the graphs in the datasheet. That requires a dedicated board for testing. This board does not have the opamps on the front end. We want to make sure to show the THD+N of just the TPA32xx device and not any other devices.

Regards,

Robert Clifton

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TPA3255: THD+N of TPA3255 from datasheet