Description

The Timer Power Unit is a compact timed power supply module for charge/discharge control, scheduled switching, status display, and boosted 5V output. It integrates an STM32 microcontroller for RTC timing and overall control, allowing automatic power-on and power-off schedules for embedded devices.

The Timer Power Unit uses Type-C for battery charging and connects to a 3.7V rechargeable lithium battery through a 1.25mm 2P battery connector. A built-in charging circuit supports 330mA charging current, while the DC-DC boost circuit can supply 5V output through the Grove port for external modules.

With an INA3221 current sensor, a 0.66-inch OLED display, two side buttons, and Grove I2C control, the Timer Power Unit lets users monitor input/output voltage and current, adjust operating modes, and build portable timed power systems.

Notice: The Timer Power Unit must be connected to a lithium battery during use. The USB Type-C interface is only for charging the battery and cannot be used directly as the output power supply.

Features

• RTC cyclic timing and timed power switching.
• Built-in lithium battery charging circuit with 330mA charging current.
• DC-DC boost output for 5V Grove-powered external devices.
• INA3221 current and voltage monitoring for input and output status.
• 0.66-inch OLED display and two side buttons for local configuration.
• Grove I2C communication for software-based setup and status reading.

Specifications

Applications

• Timed control devices that need automatic power-on and power-off schedules.
• Portable electronic devices powered by rechargeable lithium batteries.
• Sensor node power supply where the Timer Power Unit provides boosted Grove output and status monitoring.
• Smart home and industrial automation projects requiring scheduled low-power operation.

Product List

• 1 x Unit TimerPWR
• 1 x HY2.0-4P Grove cable (20cm)

Other Content

Before deployment, select a lithium battery with suitable capacity and discharge capability for the expected Grove load. The Timer Power Unit is especially useful when a system needs to remain off most of the time and wake only at scheduled intervals.

Resources

TimerPWR document

TimerPWR schematic PDF

INA3221 current and voltage monitor datasheet

LGS4056H battery charger datasheet

M5Unit-TimerPWR Arduino library

TimerPWR UiFlow2 API documentation

TimerPWR internal firmware repository

TimerPWR I2C protocol PDF

FAQ

Can it run without a lithium battery?

No. The Timer Power Unit must be connected to a lithium battery during use because the Type-C port is only for charging.

Can the Type-C port directly power Grove output?

No. The Type-C port charges the battery, while the boosted 5V output is provided through the Grove port from the battery-powered circuit.

How is the timing function configured?

The Timer Power Unit can be configured with its side buttons or through Grove I2C commands for timed power control.