Hardware Details

Hardware specifications

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Pinout

Layout

Dimension

Power Inputs/Outputs

Inputs/Outputs	Description
J3	USB Type-C 5V 3A max. input
J4	Terminal Block 5V to 21V. 4A max. current input.
J7	5V rated 2.6A max output, solderable pads on the bottom side.

🔍 Info

The recommended input voltage is 5V and the input current is 2A minimum. For the 12V input voltage, the minimum is 1.5A. We recommend the official Raspberry Pi power supply.

An external device can be connected to J7 for 5V output(underneath the HAT) and be aware of the polarity when sourcing via J7.

📖 Note

Use only one of these two inputs(J3, J4) at a time, i.e. do not plug a USB(J3) adapter while a power source is inserted through the terminal block(J4) or the other way.

The UPS HAT has several Battery input options such as J5, J9. Do not use multiple batteries at a time.

Battery(Not Included)

The HAT comes with an integrated Protected 18650 Li-on battery holder without a battery.

You can plug an external single-cell 3.7V Li-on or Li-po rechargeable batteries when bigger capacities or special dimensions are needed at J5(using Battery Cable JST-SFH) or J9 connector.

Battery Discharge Time

For 3500 mAh Battery

Device / Task	Idling	With Base HAT 4G Connection - Idle	With Cellular IoT HAT Cellular Connection - Idle
Raspberry Pi 4 (2 GB)	5 Hrs 36 Min	4 Hrs 35 Min	4 Hrs 45 Min
Raspberry Pi 3B+ (1 GB)	5 Hrs 58 Min	5 Hrs 3 Min	5 Hrs 29 Min

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.

Behavior	Status
S1(Long Press)	Hard shutdown by cutting power of Raspberry Pi
S1(Short Press)	Hard boot-up by powering Raspberry Pi
S2(Short Press)	Soft Power On. Power on if power conditions are alright*

* The pogo pin needs to be soldered for soft power on. Click more details.

LEDs

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

LED	Status
PWR	This red LED is ON when the Raspberry Pi is powered.
L1	Can be programmed as shows temperature level or heartbeat for the system.
L2	Used for battery charging level and status by default. Blinks if charging the battery, steady if the system powered by battery or fully charged

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%.

I2C Address

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.

Default Settings

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

Properties	Value
WATCHDOG_STATUS	WATCHDOG_PASSIVE
RGB_ANIM_TYPE	RGB_DISABLED
RGB_ANIM_COLOR	RED
RGB_ANIM_SPEED	RGB_FAST
BATTERY_MAX_CHARGE_LEVEL	100
BATTERY_DESIGN_CAP	2500
BATTERY_WAKEUP_STATUS	WAKEUP_PASSIVE
POWER_STATUS	RPI_POWER_ON
LOW_POWER_MODE	LPM_DISABLED
FAN_MODE	FAN_ON_MODE
WATCHDOG_INTERVAL	4 minutes
DEVICE_CURRENT_THRESHOLD	250 mA
BATTERY_CUT_OFF_TEMP	65
WAKE_UP_TOLERANCE	5%
MAX_CHARGE_TOLERANCE	2%
POWER_OUTAGE_EVENT	POWER_OUTAGE_EVENT_DISABLED
RUNTIME_ON_POWER_OUTAGE	5 minutes
SLEEPTIME_ON_POWER_OUTAGE	25 minutes