molecule
PCA9306 Level Shifter Molecule
Public Made by Adomby adom
Bidirectional 2-channel I2C/SMBus voltage-level translator molecule (TI PCA9306DCUR) — 1.8 V <-> 3.3 V, no one-shot ACK contention, 24x16 mm 4-pin Adom workcell molecule with 8 medium machine contacts
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README.mdadded+49@@ -0,0 +1,49 @@+# PCA9306 Level Shifter Molecule — Plan++## Brief+Drop-in I²C / SMBus voltage-level translator molecule for Adom workcells. Bridges a 1.8 V bus to a 3.3 V (or up to 5 V) bus with no direction pin and **no one-shot accelerator contention** — the canonical replacement for the TXS0108E on the Bosch sensortec arm board, where the TXS family's one-shot rising-edge accelerator fights I²C slave open-drain ACK pull-down and produces address-NACK at probe time.++## Decisions+- **Tool:** adom-tsci / tscircuit (canonical Adom path).+- **Size:** `24x16` — 4-pin molecule. Wider than tall so 4 + 4 perimeter contacts fit comfortably.+- **Pin grid:** medium machine pins (4 corner pins + 4 edge contacts per long side).+- **IC:** TI PCA9306DCUR in VSSOP-8 (DCU package). LCSC C58662 (JLC extended).+- **EN handling:** internally tied to VREF2 via a 10 kΩ pull-up (always-enabled by default). Cut the R5 trace if external EN control is needed later.+- **Pull-ups:** 4.7 kΩ on SDA1, SCL1 → VREF1; 4.7 kΩ on SDA2, SCL2 → VREF2. UNI-ROYAL 0402 (LCSC C25900 — JLC basic).+- **Decoupling:** one 100 nF 0402 X7R on each VREF rail, placed within 1 mm of the IC pin. Samsung CL05B104KO5NNNC (LCSC C1525 — JLC basic).+- **Top silkscreen:** "PCA9306", function tag, pin labels on every contact.+- **Bottom silkscreen:** part name, "1.8V <-> 3.3V I2C", version + author + date.++## Components+| Ref | Value | Package | MPN | LCSC |+|-----|-------|---------|-----|------|+| U1 | PCA9306DCUR | VSSOP-8 | PCA9306DCUR | C58662 |+| C1, C2 | 100 nF 25 V X7R | 0402 | CL05B104KO5NNNC | C1525 |+| R1..R4 | 4.7 kΩ 1 % | 0402 | 0402WGF4701TCE | C25900 |+| R5 | 10 kΩ 1 % | 0402 | 0402WGF1002TCE | C25744 |++## Workcell interface (8 medium machine contacts)+| Pin | Net | Side | Notes |+|-----|-------|-------|-------|+| MC_VREF1 | VREF1 | left (LV) | 1.71–1.89 V supply |+| MC_SDA1 | SDA1 | left | 1.8 V SDA, 4.7 kΩ to VREF1 |+| MC_SCL1 | SCL1 | left | 1.8 V SCL, 4.7 kΩ to VREF1 |+| MC_GND1 | GND | left | shared ground |+| MC_VREF2 | VREF2 | right (HV) | 3.3 V supply |+| MC_SDA2 | SDA2 | right | 3.3 V SDA, 4.7 kΩ to VREF2 |+| MC_SCL2 | SCL2 | right | 3.3 V SCL, 4.7 kΩ to VREF2 |+| MC_GND2 | GND | right | shared ground |++## Don'ts+- No BGA / 0201.+- No external EN pin.+- Only one JLC extended part (U1 itself); everything else basic-tier.++## Publish+```bash+cd ~/project/adom-tsci-projects/pca9306-level-shifter+bun install+bunx tsci build lib/index.tsx --glbs --svgs --3d-png --pcb-png+adom-tsci start .+adom-tsci export-wiki --slug pca9306-level-shifter --page-type molecules+```
page.jsonadded+74@@ -0,0 +1,74 @@+{+ "schema_version": 1,+ "type": "component",+ "slug": "pca9306-level-shifter",+ "title": "PCA9306 Level Shifter Molecule",+ "brief": "Bidirectional 2-channel I2C/SMBus voltage-level translator molecule (TI PCA9306DCUR) — 1.8 V <-> 3.3 V, no one-shot ACK contention, 24x16 mm 4-pin Adom workcell molecule with 8 medium machine contacts",+ "version": "2.0.0",+ "tags": [],+ "license": "MIT",+ "discovery_triggers": [+ "PCA9306",+ "level shifter",+ "I2C level translator",+ "1.8V to 3.3V I2C",+ "bidirectional I2C",+ "voltage translator",+ "TXS0108E replacement",+ "TXS0108 alternative",+ "I2C ACK NACK",+ "one-shot accelerator",+ "BHI360 level shifter",+ "PCA9306DCUR",+ "VSSOP-8",+ "castellated breakout",+ "Adom molecule level shifter"+ ],+ "discovery_pitch": "PCA9306 level shifter molecule — 1.8 V to 3.3 V bidirectional I2C, drop-in fix for TXS0108E one-shot ACK contention, JLC-ready Gerbers and BOM included.",+ "sample_prompts": [+ {+ "label": "I2C 1.8V to 3.3V",+ "prompt": "Show me a 1.8V to 3.3V I2C level shifter molecule"+ },+ {+ "label": "PCA9306 breakout",+ "prompt": "Open the PCA9306 level shifter molecule"+ },+ {+ "label": "Replace TXS0108E",+ "prompt": "What molecule replaces a TXS0108E without the one-shot ACK contention?"+ },+ {+ "label": "Order from JLC",+ "prompt": "I want to order the PCA9306 level shifter molecule from JLC"+ },+ {+ "label": "Show the 3D viewer",+ "prompt": "Open the live 3D viewer for the PCA9306 level shifter"+ }+ ],+ "component": {+ "mpn": "PCA9306 Level Shifter Molecule",+ "manufacturer": "",+ "package": "",+ "pin_count": null,+ "category": "molecule",+ "subcategory": "",+ "body_size": null,+ "parts": {},+ "distributor_links": {}+ },+ "readme": "# PCA9306 Level Shifter Molecule — Plan\n\n## Brief\nDrop-in I²C / SMBus voltage-level translator molecule for Adom workcells. Bridges a 1.8 V bus to a 3.3 V (or up to 5 V) bus with no direction pin and **no one-shot accelerator contention** — the canonical replacement for the TXS0108E on the Bosch sensortec arm board, where the TXS family's one-shot rising-edge accelerator fights I²C slave open-drain ACK pull-down and produces address-NACK at probe time.\n\n## Decisions\n- **Tool:** adom-tsci / tscircuit (canonical Adom path).\n- **Size:** `24x16` — 4-pin molecule. Wider than tall so 4 + 4 perimeter contacts fit comfortably.\n- **Pin grid:** medium machine pins (4 corner pins + 4 edge contacts per long side).\n- **IC:** TI PCA9306DCUR in VSSOP-8 (DCU package). LCSC C58662 (JLC extended).\n- **EN handling:** internally tied to VREF2 via a 10 kΩ pull-up (always-enabled by default). Cut the R5 trace if external EN control is needed later.\n- **Pull-ups:** 4.7 kΩ on SDA1, SCL1 → VREF1; 4.7 kΩ on SDA2, SCL2 → VREF2. UNI-ROYAL 0402 (LCSC C25900 — JLC basic).\n- **Decoupling:** one 100 nF 0402 X7R on each VREF rail, placed within 1 mm of the IC pin. Samsung CL05B104KO5NNNC (LCSC C1525 — JLC basic).\n- **Top silkscreen:** \"PCA9306\", function tag, pin labels on every contact.\n- **Bottom silkscreen:** part name, \"1.8V <-> 3.3V I2C\", version + author + date.\n\n## Components\n| Ref | Value | Package | MPN | LCSC |\n|-----|-------|---------|-----|------|\n| U1 | PCA9306DCUR | VSSOP-8 | PCA9306DCUR | C58662 |\n| C1, C2 | 100 nF 25 V X7R | 0402 | CL05B104KO5NNNC | C1525 |\n| R1..R4 | 4.7 kΩ 1 % | 0402 | 0402WGF4701TCE | C25900 |\n| R5 | 10 kΩ 1 % | 0402 | 0402WGF1002TCE | C25744 |\n\n## Workcell interface (8 medium machine contacts)\n| Pin | Net | Side | Notes |\n|-----|-------|-------|-------|\n| MC_VREF1 | VREF1 | left (LV) | 1.71–1.89 V supply |\n| MC_SDA1 | SDA1 | left | 1.8 V SDA, 4.7 kΩ to VREF1 |\n| MC_SCL1 | SCL1 | left | 1.8 V SCL, 4.7 kΩ to VREF1 |\n| MC_GND1 | GND | left | shared ground |\n| MC_VREF2 | VREF2 | right (HV) | 3.3 V supply |\n| MC_SDA2 | SDA2 | right | 3.3 V SDA, 4.7 kΩ to VREF2 |\n| MC_SCL2 | SCL2 | right | 3.3 V SCL, 4.7 kΩ to VREF2 |\n| MC_GND2 | GND | right | shared ground |\n\n## Don'ts\n- No BGA / 0201.\n- No external EN pin.\n- Only one JLC extended part (U1 itself); everything else basic-tier.\n\n## Publish\n```bash\ncd ~/project/adom-tsci-projects/pca9306-level-shifter\nbun install\nbunx tsci build lib/index.tsx --glbs --svgs --3d-png --pcb-png\nadom-tsci start .\nadom-tsci export-wiki --slug pca9306-level-shifter --page-type molecules\n```\n",+ "author": {+ "id": "695820315b5f1e4db2fcf602",+ "name": "Kyle Bergstedt",+ "email": "[email protected]"+ },+ "visibility": {+ "public": true+ },+ "hero": null,+ "metadata": {},+ "created_at": "2026-05-28T05:30:50.078Z",+ "updated_at": "2026-05-28T05:30:50.078Z"+}