PMIC 2 Click

How does it work?

PMIC 2 Click is based on the NEH7100, an inductorless power management IC from Nexperia designed for energy harvesting in low-power applications. Optimized for harvesting energy from a wide range of light sources, including indoor and outdoor photovoltaic cells connected to VIN pins, the device can also use other sources such as kinetic movement, vibrations, thermal variations, and electromagnetic fields with the aid of external auxiliary components. The NEH7100 collects energy from a suitable harvester to charge a storage element (connected on VBAT), such as a rechargeable battery or a supercapacitor, while Nexperia’s advanced maximum power point tracking (MPPT) technology, employing an embedded hill-climbing algorithm, ensures maximum power delivery to the storage element.

This MPPT operates with any compatible harvester and can update as frequently as every 0.5 seconds, delivering exceptional performance even under rapidly changing light or environmental conditions. The device integrates multiple auxiliary features, including storage element protection, USB charging capability of up to 200mA, and an LDO/load switch for flexible power distribution. Its ideal for a wide range of applications such as smart remote controls for TVs, gaming, and AV equipment, wireless PC peripherals including keyboards, mice, and headphones, industrial sensors like electronic shelf labels, asset trackers, and beacons, tire pressure monitoring systems, and wearable devices such as watches, body bands, and health monitoring equipment.

This Click board™ is designed in a unique format supporting the newly introduced MIKROE feature called "Click Snap." Unlike the standardized version of Click boards, this feature allows the main sensor/IC/module area to become movable by breaking the PCB, opening up many new possibilities for implementation. Thanks to the Snap feature, the NEH7100 can operate autonomously by accessing its signals directly on the pins marked 1-8. Additionally, the Snap part includes a specified and fixed screw hole position, enabling users to secure the Snap board in their desired location.

PMIC 2 Click can be configured either through hard-coding jumpers (HC SEL) or via an I2C interface operating at 100kHz, providing flexibility in setup and integration. In addition to the standard I2C communication pins, the board also features dedicated control and status signals from the NEH7100, such as the DIS pin, which places the device into a low-power consumption mode, and the BOK pin, which serves as an indicator that the battery voltage is above the configured low-voltage detection (LVD) threshold. For extended accessibility to the PMIC’s capabilities, PMIC 2 Click incorporates an additional header (J2) that exposes multiple useful signals, including BOK, DIS, LEN for enabling the LDO regulator, VLDO as the regulated LDO output, and VBAT, which outputs the harvested energy and serves as the power supply input for the PMIC.

This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. It also comes equipped with a library containing functions and example code that can be used as a reference for further development.

Hard-code settings

When using the hard-coded jumper selection (HC SEL), the PMIC 2 Click allows users to define key battery protection parameters directly on the board. These settings determine how the NEH7100 manages charging thresholds, low-voltage detection, and overall storage-element safety. For choosing the correct configuration for your battery, consult the NEH7100 datasheet (Chapter 7.3.7, Table 19), which provides the detailed battery-protection options and valid HC SEL combinations.

Click Snap

Click Snap is an innovative feature of our standardized Click add-on boards, designed to bring greater flexibility and optimize your prototypes. By simply snapping the PCB along predefined lines, you can easily detach the main sensor/IC/module area, reducing the overall size, weight, and power consumption - ideal for the final phase of prototyping. For more details about Click Snap, visit the official page dedicated to this feature.

Specifications

Pinout diagram

This table shows how the pinout on PMIC 2 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	DIS	Device Enable
	NC	2	RST	INT	15	BOK	Battery Status
	NC	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	NC	5	MISO	SCL	12	SCL	I2C Clock
	NC	6	MOSI	SDA	11	SDA	I2C Data
Power Supply	3.3V	7	3.3V	5V	10	NC
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

PMIC 2 Click electrical specifications

Software Support

PMIC 2 Click demo application is developed using the NECTO Studio, ensuring compatibility with mikroSDK's open-source libraries and tools. Designed for plug-and-play implementation and testing, the demo is fully compatible with all development, starter, and mikromedia boards featuring a mikroBUS™ socket.

Example Description

This example demonstrates the use of the PMIC 2 Click board. The board is designed to efficiently harvest energy from high-impedance sources such as solar panels. The demo reads and logs status flags and battery health indicators, including over-voltage, under-voltage, output current protection, and chip status. It also measures and logs the battery charging current in microamperes.

Key Functions

• pmic2_cfg_setup This function initializes Click configuration structure to initial values.
• pmic2_init This function initializes all necessary pins and peripherals used for this Click board.
• pmic2_default_cfg This function executes a default configuration of PMIC 2 Click board.
• pmic2_get_charge_current This function reads the charge current measurement and calculates the current value in milliamps.
• pmic2_get_bok_pin This function reads the logic state of the BOK pin.

Application Init

Initializes the logger and the PMIC 2 Click driver and applies the default configuration.

Application Task

Periodically checks and logs status flags, battery OK signal, and charging current.

Application Output

This Click board can be interfaced and monitored in two ways:

• Application Output - Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
• UART Terminal - Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.

Additional Notes and Information

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.