c131a97ac4
- W5500 SPI Ethernet controller for wired connectivity - Silvertel Ag9905MT PoE PD module (48V to 5V) - RJ45 connector with integrated magnetics - Higher camera resolution (1024x768 vs 800x600) using wired bandwidth - WiFi fallback if Ethernet disconnected - Separate BOM, pin mapping, ESPHome config - 3D-printable enclosure (50x40mm, larger for RJ45)
110 lines
2.9 KiB
Markdown
110 lines
2.9 KiB
Markdown
# Presence Sensor - PoE Variant
|
|
|
|
Same sensors as the USB-C version, but powered and networked via Power over Ethernet (802.3af).
|
|
|
|
## Key Differences from USB-C Version
|
|
|
|
| Feature | USB-C Version | PoE Version |
|
|
|---------|--------------|-------------|
|
|
| Power | USB-C 5V | 802.3af PoE (48V → 5V) |
|
|
| Network | WiFi only | Ethernet (wired) + WiFi fallback |
|
|
| Connector | USB-C | RJ45 |
|
|
| Extra chips | None | W5500 (Ethernet) + AG9905MT (PoE PD) |
|
|
| Board size | 45x35mm | 50x40mm (RJ45 is bulky) |
|
|
| Reliability | WiFi dependent | Wired, rock-solid |
|
|
| Cost | ~$32 | ~$42 |
|
|
|
|
## Why PoE is Better for Cameras
|
|
|
|
- **No WiFi congestion** - camera streams are bandwidth-heavy
|
|
- **Single cable** - power + data in one Ethernet run
|
|
- **More reliable** - no WiFi dropouts
|
|
- **Centralized power** - PoE switch manages all device power
|
|
- **Remote reboot** - cycle PoE port to hard-reset device
|
|
|
|
## New Components
|
|
|
|
### W5500 Ethernet Controller
|
|
- SPI interface to ESP32-S3
|
|
- 10/100 Mbps Ethernet
|
|
- Hardware TCP/IP stack (offloads ESP32)
|
|
- QFP-48 package (7x7mm)
|
|
- JLCPCB: C32843
|
|
|
|
### RJ45 with Integrated Magnetics + PoE
|
|
- HR911105A or equivalent
|
|
- Includes PoE center-tap connections
|
|
- Through-hole (adds height but very robust)
|
|
|
|
### PoE PD Module - Silvertel Ag9905MT
|
|
- IEEE 802.3af compliant (up to 13W)
|
|
- 48V input → 5V/2A output
|
|
- Tiny module: 16.5x14.5mm
|
|
- Isolated, protected
|
|
- Alternative: AG9905M-R or TI TPS2376 discrete
|
|
|
|
### 25MHz Crystal Oscillator
|
|
- Required by W5500
|
|
- 3.2x2.5mm SMD package
|
|
|
|
## GPIO Changes for PoE Variant
|
|
|
|
| GPIO | USB-C Version | PoE Version |
|
|
|------|--------------|-------------|
|
|
| GPIO19 | USB D- | **Free** (no USB) |
|
|
| GPIO20 | USB D+ | **Free** (no USB) |
|
|
| GPIO33 | Free | **W5500 SPI MISO** |
|
|
| GPIO34 | Free | **W5500 SPI MOSI** |
|
|
| GPIO35 | Free | **W5500 SPI SCK** |
|
|
| GPIO36 | Free | **W5500 SPI CS** |
|
|
| GPIO37 | Free | **W5500 INT** |
|
|
| GPIO42 | Free | **W5500 RST** |
|
|
|
|
Camera, mmWave, PIR, I2C sensors - all unchanged.
|
|
|
|
## Power Path
|
|
|
|
```
|
|
PoE Switch (48V)
|
|
│
|
|
▼
|
|
RJ45 Connector (center-taps)
|
|
│
|
|
▼
|
|
Ag9905MT PoE PD Module
|
|
│ (48V → 5V isolated)
|
|
▼
|
|
5V Rail ──→ LD2410C (direct)
|
|
│
|
|
▼
|
|
AMS1117-3.3
|
|
│
|
|
▼
|
|
3.3V Rail ──→ ESP32-S3, W5500, sensors, camera LDOs
|
|
```
|
|
|
|
## Power Budget (PoE)
|
|
|
|
| Component | Voltage | Current |
|
|
|-----------|---------|---------|
|
|
| ESP32-S3 | 3.3V | 240mA |
|
|
| W5500 | 3.3V | 132mA |
|
|
| OV5640 | 2.8V+1.8V | 140mA |
|
|
| LD2410C | 5V | 60mA |
|
|
| AM312 + SHT41 + BH1750 | 3.3V | 3mA |
|
|
| Ag9905MT overhead | - | ~50mA |
|
|
| **Total from PoE** | 48V | **~180mA @ 48V (~8.6W)** |
|
|
|
|
Well within 802.3af's 12.95W limit.
|
|
|
|
## Board Layout Notes
|
|
|
|
- RJ45 connector at bottom (cable exits down for wall mount)
|
|
- Ag9905MT module near RJ45 (short high-voltage traces)
|
|
- W5500 between RJ45 and ESP32 (short SPI traces)
|
|
- Camera at top (unchanged)
|
|
- mmWave on right (unchanged)
|
|
- PIR on left (unchanged)
|
|
- Sensors on left edge (unchanged)
|
|
- Board slightly larger: 50x40mm to accommodate RJ45 jack height
|