# Placement rules (derived)

| type | constraint | weight | why |
|---|---|---|---|
| fixed | J1 |  | connector (mechanical interface) |
| fixed | H3 |  | mechanical (mounting hole / no net) |
| fixed | J3 |  | connector (mechanical interface) |
| fixed | H1 |  | mechanical (mounting hole / no net) |
| fixed | J5 |  | connector (mechanical interface) |
| fixed | H4 |  | mechanical (mounting hole / no net) |
| fixed | H2 |  | mechanical (mounting hole / no net) |
| fixed | J4 |  | connector (mechanical interface) |
| fixed | J2 |  | connector (mechanical interface) |
| loop | loop U5.2 → C1.1 → C1.2 → U5.7 ≤ 6.0 mm² | 20.0 | buck U5 input hot loop via C1 |
| near | C1.1 ≤ 1.5 mm from U5.2 | 15.0 | buck U5 input cap |
| near | L1.1 ≤ 2.0 mm from U5.8 | 15.0 | buck U5 switch node short |
| near | C7.1 ≤ 3.0 mm from L1.2 | 8.0 | buck U5 output cap 47uF at the inductor |
| near | C8.1 ≤ 3.0 mm from L1.2 | 8.0 | buck U5 output cap 47uF at the inductor |
| near | C11.1 ≤ 3.0 mm from L1.2 | 8.0 | buck U5 output cap 4.7uF at the inductor |
| near | R6.2 ≤ 2.5 mm from U5.5 | 6.0 | buck U5 feedback divider |
| near | R7.1 ≤ 2.5 mm from U5.5 | 6.0 | buck U5 feedback divider |
| apart | net BUCK_FB ≥ 1.0 mm from net BUCK_SW | 5.0 | buck U5 FB away from switch node |
| loop | loop U6.4 → C11.1 → C11.2 → U6.2 ≤ 6.0 mm² | 20.0 | buck U6 input hot loop via C11 |
| near | C11.1 ≤ 1.5 mm from U6.4 | 15.0 | buck U6 input cap |
| near | L2.1 ≤ 2.0 mm from U6.3 | 15.0 | buck U6 switch node short |
| near | C12.1 ≤ 3.0 mm from L2.2 | 8.0 | buck U6 output cap 10uF at the inductor |
| near | C13.1 ≤ 3.0 mm from L2.2 | 8.0 | buck U6 output cap 10uF at the inductor |
| near | C75.1 ≤ 3.0 mm from L2.2 | 8.0 | buck U6 output cap 4.7uF at the inductor |
| near | C76.1 ≤ 3.0 mm from L2.2 | 8.0 | buck U6 output cap 4.7uF at the inductor |
| near | R10.2 ≤ 2.5 mm from U6.5 | 6.0 | buck U6 feedback divider |
| near | R11.1 ≤ 2.5 mm from U6.5 | 6.0 | buck U6 feedback divider |
| apart | net BUCK3_FB ≥ 1.0 mm from net BUCK3_SW | 5.0 | buck U6 FB away from switch node |
| near | C60.1 ≤ 1.85 mm from U7.5 (pad edge to edge) | 12.0 | U7 output cap 10uF at VOUT (regulator stability) |
| near | C18.1 ≤ 1.85 mm from U8.5 (pad edge to edge) | 12.0 | U8 output cap 2.2uF at OUT (regulator stability) |
| near | C26.1 ≤ 0.85 mm from U9.5 (pad edge to edge) | 10.0 | decoupling U9 VIO (+3V3), 100nF |
| near | C71.1 ≤ 0.85 mm from U1.27 (pad edge to edge) | 10.0 | decoupling U1 VDD (+3V3), 100nF |
| near | C72.1 ≤ 0.85 mm from U1.50 (pad edge to edge) | 10.0 | decoupling U1 VDD (+3V3), 100nF |
| near | C73.1 ≤ 0.85 mm from U1.75 (pad edge to edge) | 10.0 | decoupling U1 VDD (+3V3), 100nF |
| near | C33.1 ≤ 0.85 mm from U2.15 (pad edge to edge) | 10.0 | decoupling U2 VCC_IO (+3V3), 100nF |
| near | C43.1 ≤ 0.85 mm from U3.15 (pad edge to edge) | 10.0 | decoupling U3 VCC_IO (+3V3), 100nF |
| near | C53.1 ≤ 0.85 mm from U4.15 (pad edge to edge) | 10.0 | decoupling U4 VCC_IO (+3V3), 100nF |
| near | C74.1 ≤ 0.85 mm from U1.100 (pad edge to edge) | 10.0 | decoupling U1 VDD (+3V3), 100nF |
| near | C15.1 ≤ 1.85 mm from U7.1 (pad edge to edge) | 10.0 | decoupling U7 VIN (+3V3), 1uF |
| near | C17.1 ≤ 1.85 mm from U8.1 (pad edge to edge) | 10.0 | decoupling U8 IN (+3V3), 1uF |
| near | C70.1 ≤ 0.85 mm from U1.6 (pad edge to edge) | 10.0 | decoupling U1 VBAT (+3V3), 100nF |
| near | C77.1 ≤ 0.85 mm from U1.11 (pad edge to edge) | 10.0 | decoupling U1 VDD (+3V3), 100nF |
| near | C78.1 ≤ 1.85 mm from U1.21 (pad edge to edge) | 10.0 | decoupling U1 VDDA (VDDA), 1uF |
| near | C79.1 ≤ 0.85 mm from U1.20 (pad edge to edge) | 10.0 | decoupling U1 VREF+ (VDDA), 100nF |
| near | C32.1 ≤ 5.35 mm from U2.8 (pad edge to edge) | 3.0 | bulk cap on V5_1 (2.2uF) near U2 (anchor chosen by proximity) |
| near | C35.1 ≤ 0.85 mm from U2.22 (pad edge to edge) | 10.0 | decoupling U2 VS (VMOT), 100nF |
| near | C45.1 ≤ 0.85 mm from U3.22 (pad edge to edge) | 10.0 | decoupling U3 VS (VMOT), 100nF |
| near | C55.1 ≤ 0.85 mm from U4.22 (pad edge to edge) | 10.0 | decoupling U4 VS (VMOT), 100nF |
| near | C36.1 ≤ 0.85 mm from U2.28 (pad edge to edge) | 10.0 | decoupling U2 VS (VMOT), 100nF |
| near | C46.1 ≤ 0.85 mm from U3.28 (pad edge to edge) | 10.0 | decoupling U3 VS (VMOT), 100nF |
| near | C56.1 ≤ 0.85 mm from U4.28 (pad edge to edge) | 10.0 | decoupling U4 VS (VMOT), 100nF |
| near | C34.1 ≤ 5.35 mm from U2.28 (pad edge to edge) | 3.0 | bulk cap on VMOT (10uF) near U2 (anchor chosen by proximity) |
| near | C44.1 ≤ 5.35 mm from U3.28 (pad edge to edge) | 3.0 | bulk cap on VMOT (10uF) near U3 (anchor chosen by proximity) |
| near | C54.1 ≤ 5.35 mm from U4.28 (pad edge to edge) | 3.0 | bulk cap on VMOT (10uF) near U4 (anchor chosen by proximity) |
| near | C21.1 ≤ 5.35 mm from U3.28 (pad edge to edge) | 3.0 | bulk cap on VMOT (100uF/50V) near U3 (anchor chosen by proximity) |
| near | C22.1 ≤ 5.35 mm from U3.22 (pad edge to edge) | 3.0 | bulk cap on VMOT (100uF/50V) near U3 (anchor chosen by proximity) |
| near | C42.1 ≤ 5.35 mm from U3.8 (pad edge to edge) | 3.0 | bulk cap on V5_2 (2.2uF) near U3 (anchor chosen by proximity) |
| near | C52.1 ≤ 5.35 mm from U4.8 (pad edge to edge) | 3.0 | bulk cap on V5_3 (2.2uF) near U4 (anchor chosen by proximity) |
| near | C4.1 ≤ 0.85 mm from U5.2 (pad edge to edge) | 10.0 | decoupling U5 VIN (VIN_P), 100nF |
| near | C2.1 ≤ 5.35 mm from U5.2 (pad edge to edge) | 3.0 | bulk cap on VIN_P (2.2uF) near U5 (anchor chosen by proximity) |
| near | C3.1 ≤ 5.35 mm from U5.2 (pad edge to edge) | 3.0 | bulk cap on VIN_P (2.2uF) near U5 (anchor chosen by proximity) |
| near | C25.1 ≤ 0.85 mm from U9.3 (pad edge to edge) | 10.0 | decoupling U9 VCC (+5V), 100nF |
| near | C16.1 ≤ 1.85 mm from U7.5 (pad edge to edge) | 10.0 | decoupling U7 VOUT (+2V8), 1uF |
| near | C61.1 ≤ 2.85 mm from U7.5 (pad edge to edge) | 3.0 | bulk cap on +2V8 (100nF) near U7 (anchor chosen by proximity) |
| near | C65.1 ≤ 0.85 mm from U8.5 (pad edge to edge) | 10.0 | decoupling U8 OUT (+1V5), 100nF |
| near | C64.1 ≤ 5.35 mm from U8.5 (pad edge to edge) | 3.0 | bulk cap on +1V5 (2.2uF) near U8 (anchor chosen by proximity) |
| closer | C61.1 closer to U7.5 than C16.1 | 2.0 | C61 (smaller) closer to U7.5 than C16 |
| closer | C16.1 closer to U7.5 than C60.1 | 2.0 | C16 (smaller) closer to U7.5 than C60 |
| closer | C65.1 closer to U8.5 than C18.1 | 2.0 | C65 (smaller) closer to U8.5 than C18 |
| closer | C45.1 closer to U3.22 than C22.1 | 2.0 | C45 (smaller) closer to U3.22 than C22 |
| closer | C36.1 closer to U2.28 than C34.1 | 2.0 | C36 (smaller) closer to U2.28 than C34 |
| closer | C46.1 closer to U3.28 than C44.1 | 2.0 | C46 (smaller) closer to U3.28 than C44 |
| closer | C44.1 closer to U3.28 than C21.1 | 2.0 | C44 (smaller) closer to U3.28 than C21 |
| closer | C56.1 closer to U4.28 than C54.1 | 2.0 | C56 (smaller) closer to U4.28 than C54 |
| closer | C4.1 closer to U5.2 than C2.1 | 2.0 | C4 (smaller) closer to U5.2 than C2 |
| near | X1.1 ≤ 4.0 mm from U1.12 | 6.0 | crystal X1 next to U1 oscillator pin |
| near | C83.1 ≤ 2.0 mm from X1.1 | 5.0 | crystal X1 load cap |
| near | X1.3 ≤ 4.0 mm from U1.13 | 6.0 | crystal X1 next to U1 oscillator pin |
| near | C84.1 ≤ 2.0 mm from X1.3 | 5.0 | crystal X1 load cap |
| near | C5.1 ≤ 2.0 mm from U1.33 | 5.0 | C5 (100nF) filters U1 PC5 (VIN_S) |
| near | C10.1 ≤ 2.0 mm from U5.6 | 5.0 | C10 (47pF) filters U5 COMP (BUCK_COMP) |
| near | C24.1 ≤ 2.0 mm from U1.32 | 5.0 | C24 (100nF) filters U1 PC4 (VAC_S) |
| near | C80.1 ≤ 2.0 mm from U1.48 | 5.0 | C80 (2.2uF) filters U1 VCAP (VCAP) |
| near | C81.1 ≤ 2.0 mm from U1.48 | 5.0 | C81 (2.2uF) filters U1 VCAP (VCAP) |
| near | C82.1 ≤ 2.0 mm from U1.14 | 5.0 | C82 (100nF) filters U1 NRST (NRST) |
| near | FB1.2 ≤ 3.0 mm from C63.1 | 2.0 | filter FB1 feeds its cap C63 |
| near | FB2.2 ≤ 3.0 mm from C78.1 | 2.0 | filter FB2 feeds its cap C78 |
| near | D10.1 ≤ 6.0 mm from J1.22 | 2.0 | D10 belongs at connector J1 (termination / protection) |
| near | R32.1 ≤ 6.0 mm from J1.23 | 2.0 | R32 belongs at connector J1 (termination / protection) |

## Review

- **WARN** UNANCHORED C14: C14 (6.8pF) has no placement rule
- **WARN** UNANCHORED C19: C19 (47nF) has no placement rule
- **WARN** WEAK_ANCHOR C2: C2 anchored only by proximity: bulk cap on VIN_P (2.2uF) near U5 (anchor chosen by proximity)
- **WARN** UNANCHORED C20: C20 (100nF) has no placement rule
- **WARN** WEAK_ANCHOR C21: C21 anchored only by proximity: bulk cap on VMOT (100uF/50V) near U3 (anchor chosen by proximity)
- **WARN** WEAK_ANCHOR C22: C22 anchored only by proximity: bulk cap on VMOT (100uF/50V) near U3 (anchor chosen by proximity)
- **WARN** UNANCHORED C23: C23 (100nF) has no placement rule
- **WARN** WEAK_ANCHOR C3: C3 anchored only by proximity: bulk cap on VIN_P (2.2uF) near U5 (anchor chosen by proximity)
- **WARN** UNANCHORED C30: C30 (22nF) has no placement rule
- **WARN** UNANCHORED C31: C31 (100nF) has no placement rule
- **WARN** WEAK_ANCHOR C32: C32 anchored only by proximity: bulk cap on V5_1 (2.2uF) near U2 (anchor chosen by proximity)
- **WARN** WEAK_ANCHOR C34: C34 anchored only by proximity: bulk cap on VMOT (10uF) near U2 (anchor chosen by proximity)
- **WARN** UNANCHORED C40: C40 (22nF) has no placement rule
- **WARN** UNANCHORED C41: C41 (100nF) has no placement rule
- **WARN** WEAK_ANCHOR C42: C42 anchored only by proximity: bulk cap on V5_2 (2.2uF) near U3 (anchor chosen by proximity)
- **WARN** WEAK_ANCHOR C44: C44 anchored only by proximity: bulk cap on VMOT (10uF) near U3 (anchor chosen by proximity)
- **WARN** UNANCHORED C50: C50 (22nF) has no placement rule
- **WARN** UNANCHORED C51: C51 (100nF) has no placement rule
- **WARN** WEAK_ANCHOR C52: C52 anchored only by proximity: bulk cap on V5_3 (2.2uF) near U4 (anchor chosen by proximity)
- **WARN** WEAK_ANCHOR C54: C54 anchored only by proximity: bulk cap on VMOT (10uF) near U4 (anchor chosen by proximity)
- **WARN** UNANCHORED C6: C6 (100nF) has no placement rule
- **WARN** WEAK_ANCHOR C61: C61 anchored only by proximity: bulk cap on +2V8 (100nF) near U7 (anchor chosen by proximity)
- **WARN** UNANCHORED C62: C62 (10uF) has no placement rule
- **WARN** WEAK_ANCHOR C64: C64 anchored only by proximity: bulk cap on +1V5 (2.2uF) near U8 (anchor chosen by proximity)
- **WARN** UNANCHORED C9: C9 (4.7nF) has no placement rule