# Standard Components with LCSC Integration

This guide describes the system for standard passive components (R, C, L) and common ICs with LCSC part numbers.

## 🎯 Objectives

- **Consistent assembly**: Always use the same, well-available parts
- **Cost optimization**: LCSC Basic Parts for low costs
- **Automation**: Direct BOM generation for JLCPCB/LCSC
- **Standardization**: Fixed value series for all projects

## 📊 Standard Component Categories

### Standard Passives (R/C/L)
- **Purpose**: Cost-optimized standard values with LCSC numbers
- **Footprints**: Use existing KiCad footprints (Resistor_SMD, Capacitor_SMD, Inductor_SMD)
- **Symbols**: Custom symbols with complete LCSC data
- **Examples**: `100nF_0603_C14663`, `10k_0603_C25804`, `100uH_0805_C1046`

### Standard ICs
- **Purpose**: Common ICs with LCSC numbers for automated assembly
- **Categories**:
  - **CAN Controllers**: MCP2515, SN65HVD230
  - **STM32 MCUs**: STM32F103C8T6, STM32F407VGT6
  - **Voltage Regulators**: AMS1117-3.3, LM2596
  - **Op-Amps**: LM358, LM324, TL074
  - **Logic**: 74HC595, 74HC4051
  - **Interface**: FT232RL, CH340G
- **Footprints**: Use existing KiCad footprints (Package_SO, Package_QFP, etc.)

## 🏷️ Naming Convention

### Symbol Names
```
Standard Passives: [Value]_[Package]_[LCSC]
Standard ICs:      [Partnumber]_[Package]_[LCSC]

Examples:
100nF_0603_C14663
10k_0603_C25804
1uF_0805_C28323
STM32F103C8T6_LQFP-48_C8734
MCP2515_SOIC-18_C55199
AMS1117-3.3_SOT-223_C6186
```

### Symbol Properties
```
Reference: R?, C?, L?, U?
Value: [Value] (e.g. "100nF", "10k", "STM32F103C8T6")
Footprint: [KiCad_Library]:[Standard_Footprint]
    Examples:
    - Resistor_SMD:R_0603_1608Metric
    - Capacitor_SMD:C_0603_1608Metric  
    - Package_SO:SOIC-18W_7.5x11.6mm_P1.27mm
    - Package_QFP:LQFP-48_7x7mm_P0.5mm
Datasheet: [LCSC-URL]
Description: [Full specification]
LCSC: [C-Number]
Manufacturer: [Manufacturer name]
MPN: [Manufacturer Part Number]
Package: [0603/SOIC-18/LQFP-48/etc.]
```

## 📋 LCSC Basic Parts Database

### Resistors (UniOhm Thick Film, 1%)
| Value | Package | LCSC | MPN | Description | Price@1k |
|-------|---------|------|-----|-------------|----------|
| 0R | 0603 | C21189 | 0603WAF0000T5E | Res 0R 1/10W 0603 | $0.002 |
| 10R | 0603 | C22859 | 0603WAF100JT5E | Res 10R 1% 1/10W 0603 | $0.002 |
| 100R | 0603 | C22775 | 0603WAF1000T5E | Res 100R 1% 1/10W 0603 | $0.002 |
| 1k | 0603 | C21190 | 0603WAF1001T5E | Res 1k 1% 1/10W 0603 | $0.002 |
| 10k | 0603 | C25804 | 0603WAF1002T5E | Res 10k 1% 1/10W 0603 | $0.002 |
| 100k | 0603 | C25803 | 0603WAF1003T5E | Res 100k 1% 1/10W 0603 | $0.002 |

### Capacitors (Samsung CL Series, X7R, 50V)
| Value | Package | LCSC | MPN | Description | Price@1k |
|-------|---------|------|-----|-------------|----------|
| 100pF | 0603 | C1524 | CL10B101KB8NNNC | Cap 100pF 50V X7R 0603 | $0.002 |
| 1nF | 0603 | C1523 | CL10B102KB8NNNC | Cap 1nF 50V X7R 0603 | $0.002 |
| 10nF | 0603 | C57112 | CL10B103KB8NNNC | Cap 10nF 50V X7R 0603 | $0.003 |
| 100nF | 0603 | C14663 | CL10B104KB8NNNC | Cap 100nF 50V X7R 0603 | $0.003 |
| 1µF | 0603 | C15849 | CL10A105KA8NNNC | Cap 1µF 25V X5R 0603 | $0.004 |
| 10µF | 0805 | C15850 | CL21A106KAQNNNE | Cap 10µF 25V X5R 0805 | $0.008 |

### Standard ICs (LCSC Basic Parts)
| Component | Package | LCSC | MPN | Description | Price@1k |
|-----------|---------|------|-----|-------------|----------|
| STM32F103C8T6 | LQFP-48 | C8734 | STM32F103C8T6 | MCU 32-bit ARM Cortex M3 | $2.89 |
| MCP2515 | SOIC-18 | C55199 | MCP2515-I/SO | CAN Controller | $1.67 |
| SN65HVD230 | SOIC-8 | C12084 | SN65HVD230DR | CAN Transceiver | $0.39 |
| AMS1117-3.3 | SOT-223 | C6186 | AMS1117-3.3 | LDO 3.3V 1A | $0.11 |
| LM358 | SOIC-8 | C7950 | LM358DR | Dual Op-Amp | $0.11 |
| 74HC595 | SOIC-16 | C5947 | 74HC595D | 8-bit Shift Register | $0.15 |
| FT232RL | SSOP-28 | C8690 | FT232RL | USB to Serial | $3.45 |

## 🗂️ Library Structure

### Symbol Libraries
```
symbols/
├── Standard_Passives.kicad_sym
│   ├── Resistors/
│   │   ├── 10R_0603_C22859
│   │   ├── 100R_0603_C22775  
│   │   ├── 1k_0603_C21190
│   │   └── ...
│   ├── Capacitors/
│   │   ├── 100nF_0603_C14663
│   │   ├── 1uF_0603_C15849
│   │   └── ...
│   └── Inductors/
│       ├── 100nH_0603_C1588
│       └── ...
└── Standard_ICs.kicad_sym
    ├── Microcontrollers/
    │   ├── STM32F103C8T6_LQFP-48_C8734
    │   └── ...
    ├── CAN/
    │   ├── MCP2515_SOIC-18_C55199
    │   ├── SN65HVD230_SOIC-8_C12084
    │   └── ...
    └── Power/
        ├── AMS1117-3.3_SOT-223_C6186
        └── ...
```

### Footprint Mapping
**Standard components use existing KiCad footprints:**

```
Resistors → Resistor_SMD:R_[Package]_[Metric]
Capacitors → Capacitor_SMD:C_[Package]_[Metric]  
Inductors → Inductor_SMD:L_[Package]_[Metric]

ICs → Package_SO:SOIC-[pins]...
     Package_QFP:LQFP-[pins]...
     Package_TO_SOT_SMD:SOT-223...
     etc.
```

## ⚙️ Workflow

### Adding New Standard Component

#### 1. Research Phase
```bash
# Check if component exists in KiCad
1. Open KiCad Symbol Editor
2. Search for component in standard libraries
3. If exists: Note library and symbol name
4. If not exists: Create custom symbol
```

#### 2. LCSC Lookup
```bash
# Find LCSC part number
1. Search component on lcsc.com
2. Check if it's a "Basic Part" (lower cost)
3. Verify stock status and pricing
4. Note: LCSC#, Manufacturer, MPN
```

#### 3. Symbol Creation
```bash
# Create symbol with LCSC data
1. Use existing KiCad symbol as template (if available)
2. Add LCSC properties:
   - LCSC: C-Number
   - Manufacturer: Company name
   - MPN: Manufacturer Part Number
3. Set footprint to standard KiCad footprint
4. Add datasheet URL
```

#### 4. Testing
```bash
# Verify in test circuit
1. Create test schematic
2. Run ERC (Electrical Rules Check)
3. Create test PCB
4. Run DRC (Design Rules Check)
5. Check 3D view
```

### BOM Generation for JLCPCB

#### Export Format
```csv
Comment,Designator,Footprint,LCSC,Manufacturer,MPN
100nF,C1;C2;C5,C_0603_1608Metric,C14663,Samsung,CL10B104KB8NNNC
10k,R1;R3;R7,R_0603_1608Metric,C25804,UniOhm,0603WAF1002T5E
STM32F103C8T6,U1,LQFP-48_7x7mm_P0.5mm,C8734,STMicroelectronics,STM32F103C8T6
```

## 🎯 Best Practices

### Component Selection Strategy
1. **Always check LCSC first**: Use Basic Parts when possible
2. **Standardize values**: Prefer E24 series for resistors
3. **Package consistency**: Use 0603 for most passives
4. **Verify availability**: Check stock before committing to design

### Cost Optimization
| Strategy | Savings | Implementation |
|----------|---------|----------------|
| Basic Parts only | 50-80% | Use LCSC Basic Parts database |
| Standard packages | 20-30% | Stick to 0603, SOIC, QFP |
| Volume planning | 10-20% | Order 1000+ pieces |
| Setup minimization | $2-5 per unique part | Reuse same values |

### Design Guidelines
- **0603 preferred**: Good balance of size/handling
- **Basic Parts first**: Always check Basic Parts availability
- **Standard values**: E24 series for resistors, E6 for capacitors
- **Safety margins**: +20% on critical values

## 🔄 Maintenance

### Regular Updates
1. **Monthly**: Check LCSC availability and pricing
2. **Quarterly**: Update Basic Parts list
3. **Per project**: Verify all parts in stock before ordering
4. **KiCad updates**: Test footprint compatibility

### Version Control
```bash
# Git workflow
git add symbols/Standard_*.kicad_sym
git commit -m "feat: add STM32F407 with LCSC C13303"
git tag -a v1.2.0 -m "Standard ICs v1.2.0"
```

---

*This document is regularly synchronized with current LCSC data.*