Reference circuit audit
Collect and cross-reference original STK datasheets, application notes, and documented failure modes.
SKY130 STK Power Module Revamp
Open-source CMOS redesign of classic Sanyo STK hybrid amplifiers
The Sanyo STK series (STK0050, STK4048XI, STK4141II and relatives) were ceramic hybrid modules that powered an entire generation of hi-fi receivers and amplifiers. With original modules now aging, scarce, and prone to failure, this project aims to recreate and modernise their core topology using the SkyWater 130 nm open-source PDK (SKY130), making the design fully reproducible and improvable by the community. The project covers schematic porting, SPICE simulation, layout in the SKY130 process, and tape-out planning through the efabless/Google chipIgnite shuttle.
Project Goals
- Audit original STK topologies from datasheets and reverse-engineering literature
- Port representative circuit (e.g. STK0050 output stage) to SKY130-compatible devices
- Run full SPICE simulations covering audio-band THD, slew rate, thermal headroom
- Produce a DRC/LVS-clean layout using Magic and the SKY130 PDK
- Submit to an efabless chipIgnite shuttle for silicon verification
Tech Stack
Milestones
SPICE model selection
Map STK bipolar and FET devices to equivalent SKY130 primitives; verify operating-point and small-signal parameters.
Schematic and simulation
Redraw the output stage in Xschem with SKY130 device models, simulate for audio performance and stability.
IC layout
Place and route in Magic VLSI, run DRC and LVS against SKY130 design rules.
Shuttle submission
Package the design for an efabless chipIgnite open-source shuttle and coordinate group buy of fabricated dies.
Open Roles
Analog IC designer
Port and tune the STK output-stage topology to SKY130 transistors; own simulation and performance verification.
Layout engineer
Produce DRC/LVS-clean layout in Magic VLSI using the SKY130 open PDK.
Vintage audio researcher
Document original STK operating conditions, typical failure modes, and application circuit context.
PCB / test board designer
Design the evaluation PCB that hosts the fabricated die carrier and recreates the original amplifier context for audio testing.
Resources
License: Apache 2.0 (to align with SKY130 PDK license)