Parts & BOM
Core Components
Section titled “Core Components”| Component | Part Number | Qty on Hand | Qty Needed | Status |
|---|---|---|---|---|
| PSoC 1 voice chip | CY8C29466-24PXI | 100+ | 16–32 | In stock (discontinued part, full supply on hand) |
| Master controller | ESP32-S3-DevKitC-1 | TBD | 1 | Available from Espressif / distributors |
| I2C multiplexer | TCA9548A | TBD | 2 | Available, ~$1.50/ea |
| PSoC programmer | CY8CKIT-002 MiniProg3 | 1 | 1 | On hand |
CY8C29466 Inventory Note
Section titled “CY8C29466 Inventory Note”The CY8C29466 is discontinued by Cypress (now Infineon). No modern equivalent exists with comparable dynamically reconfigurable analog fabric. The 100+ unit inventory represents the full supply for this project — enough for development, production of multiple instruments, and spares.
These were acquired specifically because this chip represents a capability that hasn’t been replicated. Field Programmable Analog Arrays (FPAAs) from Anadigm are the closest modern alternative but lack an onboard CPU and add system complexity that the PSoC 1’s integrated M8C core avoids.
Support Components (Phase 1)
Section titled “Support Components (Phase 1)”| Component | Purpose | Notes |
|---|---|---|
| Decoupling capacitors | PSoC power supply filtering | 100nF ceramic + 10μF electrolytic per chip |
| Crystal oscillator | PSoC clock source | 24MHz, if external clock needed (internal oscillator may suffice for PoC) |
| Level shifters | TOS divider input (optional) | Resistor dividers or BSS138-based bidirectional level shifters |
| Op-amp | Output summing mixer | TL074 or similar quad JFET-input op-amp for low noise |
| Output filter | SC clock noise rejection | Continuous-time 2nd-order Sallen-Key LPF, cutoff ~40kHz |
PCB (Future Phases)
Section titled “PCB (Future Phases)”Voice board PCBs will be designed after Phase 1 characterization is complete. The target is 4 CY8C29466 chips per board with:
- Individual I2C address selection (jumper or solder bridge)
- Per-voice audio output header
- Onboard summing bus
- Power regulation (3.3V for PSoC digital, 5V for PSoC analog)
- Expansion connector for daisy-chaining boards
Audio Output Stage (TBD)
Section titled “Audio Output Stage (TBD)”The output stage topology will be determined after Phase 2, based on noise measurements and mixing requirements. Options under consideration:
| Topology | Pros | Cons |
|---|---|---|
| Per-voice individual outputs | Maximum flexibility, Eurorack-compatible | Requires many jacks, complex panel |
| Stereo mix bus only | Simple, conventional | Loses per-voice spatial control |
| Both (normalled) | Individual outs available, falls back to mix bus when unplugged | Most hardware, most flexible |
The “both with normalling” approach is the likely outcome — each voice has a jack that, when nothing is plugged in, routes to the stereo mix bus. Plugging in a cable breaks the normal and gives direct access to that voice.
Tools & Software
Section titled “Tools & Software”| Tool | Purpose | Notes |
|---|---|---|
| PSoC Designer | CY8C29466 firmware development | Legacy Cypress IDE, Windows only |
| Arduino IDE / PlatformIO | ESP32-S3 firmware | Standard toolchain |
| KiCad | PCB design | Voice boards, output stage |
| LTspice | Circuit simulation | Output filter, audio stage |