Expand: Media I/O 1.0
Expand: Media I/O 1.0 datasheet — speaker, microphone, microSD storage, audio and storage interfaces, and connectors.
Datasheet for Expand: Media I/O 1.0, the Attaky media-kit expansion module. For the user guide, see the Media I/O manual. System-wide pin maps and the global I²C address table are on Frame & Connections.
Features
- Mono Class-D speaker amplifier (NS4168) over I2S
- Bottom-port digital MEMS microphone (ICS-43434) over I2S
- Push-in microSD card slot for storage
- Single-rail audio in and out plus removable storage, all carried over the back board-to-board connector
Components
| Part | Role | Interface |
|---|---|---|
| NS4168 | Mono Class-D audio amplifier (speaker out) | I2S |
| ICS-43434 | Digital MEMS microphone (audio in) | I2S |
| Push-in microSD slot | Removable storage | SD (1-bit) |
Specifications
| Item | Value |
|---|---|
| Speaker amplifier | NS4168, mono Class-D, I2S |
| Speaker SNR | 85 dB |
| Microphone | ICS-43434, omnidirectional MEMS, I2S |
| Microphone SNR | 64 dB |
| Storage | Push-in microSD slot, SD interface |
| Audio bus | I2S (speaker and microphone on separate clock lines) |
Audio
- Speaker out — NS4168, a mono Class-D amplifier driven over I2S. It carries an anti-distortion path that reduces the influence of noise sources on the transmitted audio. Rated SNR is 85 dB.
- Microphone in — ICS-43434, an omnidirectional bottom-port digital MEMS microphone over I2S, with a 64 dB SNR. Sensitivity tolerance is tight enough that no system-level microphone calibration is required.
The speaker and microphone run on independent I2S clock lines — the speaker on its own bit clock (BCLK) and left-right clock (LRCLK), the microphone on its own bit clock (SCK) and word-select (WS) — each with its own data line (speaker SDATA, microphone SD).
Storage
A push-in microSD card slot, exposed over the SD interface (CLK / CMD / DAT0, with card detect on DAT3). microSD card not included.
Controls & sensors
None. Media I/O carries no buttons, keys, or sensors — all of its facilities (audio I/O and storage) run through the Core.
Connectors & power
Media I/O attaches through the back board-to-board (BTB) connector only — it has no top, side, or bottom expansion IO.
Each chip pin lands on a BTB position:
| Chip | Pin | Connector |
|---|---|---|
| microSD slot | CLK | M-BTB26 |
| microSD slot | CMD | M-BTB27 |
| microSD slot | DAT0 | M-BTB28 |
| microSD slot | CD / DAT3 | M-BTB33 |
| NS4168 amplifier | BCLK | M-BTB31 |
| NS4168 amplifier | SDATA | M-BTB32 |
| NS4168 amplifier | LRCLK | M-BTB39 |
| ICS-43434 microphone | WS | M-BTB38 |
| ICS-43434 microphone | SD | M-BTB30 |
| ICS-43434 microphone | SCK | M-BTB42 |
| ICS-43434 microphone | LR | M-BTB37 |
For the complete connector pin map (every BTB position) and the system-wide I²C table, see Frame & Connections.
Mechanical
| Item | Value |
|---|---|
| Module body | 66 × 46 mm |
| Thickness | 8.5 mm |
Operating conditions
| Item | Value |
|---|---|
| Operating temperature | 0–40 °C (32–104 °F) |
| Water resistance | None — not waterproof, no IP rating |
Keep it dry, out of direct sunlight, and away from prolonged heat — do not leave it in a parked car.