Hardware Details

Hardware specifications

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Pinout

Layout

Dimension

3D Files

You can download the 3D design files of the Sixfab Power Management UPS HAT from github repository.

Power Inputs/Outputs

Battery(Not Included)

The HAT comes with an integrated Protected 18650 Li-on battery holder without a battery. It can be breakable if needed to use it in a different placement. Then you need to use the battery cable included in the package to connect the battery to the mainboard via JST- SFH connectors(J5 and J10)

You can plug an external single-cell 3.7V Li-on or Li-po rechargeable batteries when bigger capacities or special dimensions needed. Use JST-SFH connector(J5) with a suitable battery cable with it or you can solder cables to battery header(J9) by paying attention to the polarity.

Battery Discharge Time

For 3500 mAh Battery

Buttons

There are two right-angle push buttons(S1,S2) at the edge of the HAT.
The default behaviors of the buttons are as follows.

LEDs

There are three LEDs on the HAT as two of them are programmable RGB.

• Blinks if charging the battery, steady if the system powered by battery or fully charged.
• The color shows the percentage of the battery.
  • RED when the lower than 30%.
  • YELLOW between 30% and 60%.
  • GREEN when the battery is charged more than 60%.

The Qwiic cable and the qwiic connectors(J1-J11) on board are used to read the temperature of the battery holder card when battery holder broke off from UPS HAT.

The UPS HAT uses 0x41 I2C address. The sensor on the battery uses 0x48 i2c address. Make sure it is not conflicting with another device using the same address.

Software Details

Software services

This installs two services,power_agent and power_request which provides communication between the UPS HAT and the Power Software Platform.

Functions dependent on the power_agent service

While using the following functions the agent service should be active.

• Functions that will trigger the HAT: soft_reboot, soft_power_off, hard_reboot, send_system_temp, send_battery_temp
• Watchdog
• Fan: auto mode

Watchdog

Watchdog is a power software dependent function. If the power_agent service shuts down or freezes in any way, it restarts the Raspberry Pi at the end of the watchdog interval value set.

If you want to use it with the Python API, after disabling the power_agent service, you can use it by sending the watchdog_signal command. If the signal is not sent to the MCU within the watchdog_interval time, it does hard_reboot. Also, get_watchdog_status should return 1 when active and the watchdog_interval can be set using set_watchdog_interval function.

Power Mode

The UPS HAT can be operated in 2 power modes as follows:

LPM(Low Power Mode)
This is an energy-saving mode. L1 LED turns off. L2 LED blinks at an interval of 10 seconds indicating the charge status.

To enable/disable the low power mode use set_lpm_status(status).

EDM (Easy Deployment Mode)
This mode is to save the battery after development to deployment.
It allows the Raspberry Pi and it’s peripherals to sleep while powered through the battery. Thus, it provides long-term use without consuming the battery before deployment.

To activate Easy Deployment Mode follow:

• Update Software and Firmware. (Minimum FW version: 0.3.0)
• Disconnect the adapter/power source(J2, J3, J4) from the HAT.
• Press the S1 button shortly 5 times. Avoid long-press!

Activating the Easy Deployment Mode will turn off all LEDs of the HAT.

Connect the power source to UPS HAT to exit EDM.

Default Settings

The default behavior of the UPS HAT is defined as follows: