I’m blocked because the account has no available ACUs, so I can’t continue executing schematic/layout changes right now.
What I completed this session:
Read the attached document and extracted the required architecture:
USB-C → CH224K PD trigger at 9 V → AL8860 buck constant-current driver → 2-pin off-board UV-C LED output
Confirmed: UV-C LED must not be placed on the PCB
Researched and identified library parts for:
CH224K USB-PD trigger
AL8860 buck LED driver
HT7333-A 3.3 V LDO
ATtiny412 SOIC-8
SS14 Schottky diode
USB-C 16-pin receptacle
UPDI header, button, status LED, interlock/output connectors
Extracted key datasheet facts:
AL8860 LED current: I = 0.1 / Rsense
0.30 Ω sets about 333 mA
CH224K 9 V request can use CFG logic or RSET configuration
HT7333-A supports 3.3 V output from 9–12 V input
ATtiny412 UPDI is on PA0 / RESET / UPDI
What remains:
Replace the current old schematic with the new CH224K + AL8860 + ATtiny412 design.
Add the exact BOM values from the document.
Add the 2-pin output connector instead of onboard UV-C LED.
Update project docs and firmware notes.
Create the under-40 × 40 mm 2-layer layout following Section 5.
General Purpose Thick Film Standard Power
and High-Power Chip Resistor
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film
Features:
- RMCF – standard power ratings
- RMCP – high power ratings
- Nickel barrier terminations standard
- Power derating from 100% at 70ºC to zero at +155ºC
- RoHS compliant, REACH compliant, and halogen free
- AEC-Q200 compliant
A momentary or non-latching switch which causes a temporary change in the state of an electrical circuit only while the switch is physically actuated. SWITCH TACTILE SPST-NO 0.05A 24V