When it stays silent
A silent TK103 is almost always one of six things, and the red LED sorts them first. Dark means no power. Lit means the board is fine and the fault is in the clocks, XSMT, the sample rate, or what is plugged into the jack. Start from the symptom, and keep a meter handy.
Symptom first
Three measurements
| Measure | With | Expect |
|---|---|---|
| 3V3 to GND on the board | power on | 3.0 to 3.6 V |
| XSMT to GND | power on, XSMT wire off | about 3.3 V |
| The red LED | power on | lit |
The first finds a missing or wrong supply; the LED only says whether there is one at all. The second proves the pull-up, so a mute is coming from your wiring or your sketch, not from the board.
Back to the first sketch
Go back to Left, then right: 44.1 kHz, 16-bit stereo, the book's GPIOs, headphones in the jack, and the XSMT wire off. Get the tone in each ear first. Then add XSMT, then your own sample rate, then your own sketch. A fault that appears at one step belongs to that step.
When it does not work
Usually the DAC ran out of samples for a moment, because loop() was busy with something else when the next buffer was due. Keep the audio loop short, move slow work out of it, and on the radio sketch keep the Wi-Fi signal strong.
With no clocks the chip mutes itself, and after a second of none it powers down. It starts again by itself as soon as the sketch sends samples; if it does not, reset the ESP32-S3 and look for a sketch that stopped writing.
Compare the begin() lines. The live-monitor sketch opens the DAC with I2S_DATA_BIT_WIDTH_32BIT, which gives 64 bit clocks per sample, the only setting TI lists at 16 kHz. 16-bit slots at 16 kHz are outside the table.
About 3.3 V against GND when nothing drives it, held there by the board's 10 kΩ. If it reads near 0 V, something is pulling it LOW and the chip is muted.
The block's reference page: its pins, specifications and downloads.
TK103 I2S DAC →Edit this page — content/books/i2s-dac/when-it-stays-silent.mdx
Questions about this product
See what other owners have asked, and read their solutions.
I2S DAC
Loading discussions…
Discuss this article
Ask about this page. The answer stays here, on the page it belongs to, for whoever hits the same wall next.