Battery Monitoring + Passthrough Power Support for RK3588

[andrescera]

🚀 Feature Request: Battery Monitoring + Passthrough Power Support for RK3588 SBCs

📌 Summary

Support battery monitoring and smart charging for RK3588-based SBCs (e.g., Orange Pi 5/5+, Rock 5B/5B+), optionally Jetson nano using a combination of:

• Fuel gauge (e.g., MAX17043)
• USB-C PD charger (e.g., BQ25792)
• Boost converters for multiple 5V/9V loads
• Safe power-path management

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🔋 Hardware Example

Battery Pack

• 3S2P Lithium-Ion (11.1V nominal, 12.6V max)
• With integrated BMS for protection

Charging IC

• ✅ BQ25792 (USB-C PD, power-path capable, I²C)

Fuel Gauge

• ✅ MAX17043 (State-of-charge + voltage over I²C)
• 🟡 Alternatives: MAX17048, BQ27441, INA219

Boost Converters

• MP1584 (5V 3A buck)
• MT3608 (step-up to 5V, ~2A)
• USB-C PD Buck Modules (e.g., ZY12PDN)

---

🔌 ASCII Diagram of Full Power Architecture

                        +-----------------------------+
                        |      USB-C Input Power      |
                        +-------------+---------------+
                                      |
                                      v
                          +----------------------+
                          |   BQ25792 Charger    |
                          | (USB-C PD + Power    |
                          |  Path Management)    |
                          +--+-------------+-----+
                             |             |
                             v             v
               +------------------+    +----------------------+
               |    Li-Ion Pack   |    |   System Load Rail   |
               |     (3S2P)       |    | (Power to Boost DC)  |
               +--------+---------+    +----------------------+
                        |                         |
                        |                         +--------------------------+
                        |                                                    |
                        v                                                    v
                +-------------+                              +----------------------+
                |  MAX17043   |                              |  Boost Converters    |
                | Fuel Gauge  |                              |  (5V / 9V as needed) |
                +-------------+                              +---+--------+--------+
                        |                                         |        |
                   I²C Bus                                   +----+    +--+--+
                        |                                    |         |     |
                        v                                    v         v     v
             +----------------+                    +-------------+ +-------------+
             |  RK3588 SBC    |                    | [Optional]   | | [Optional]   |
             | (e.g. OPI 5+)  |                    | USB Device 1 | | USB Device 2 |
             +----------------+                    +-------------+ +-------------+

---

🛠 Minimal Features Required

• Read battery % (SoC), voltage, and charge/discharge status from I²C
• Use i2c-bus or similar npm package
• Provide battery data to:
  • WebSocket
• Optionally integrate with:
  • UPower or custom systemd service
  • D-Bus messages for battery events
  • Graceful shutdown hooks when battery is low & no external power is being applied

---

💡 Alternative Components

Component Type	Recommended	Alternatives
Charger IC	BQ25792	BQ24295, IP5306, BQ25620
Fuel Gauge	MAX17043	MAX17048, BQ27441, INA219
Boost Module	MP1584, MT3608	TPS61088, PD Buck modules
Comm Protocol	I²C via Node.js	Python (smbus), C (libi2c)

---

🔗 References

• MAX17043 Datasheet
• BQ25792 Datasheet
• i2c-bus NPM Module
• Orange Pi 5 Plus Wiki
• Rockchip RK3588 SoC Overview