Current Limit 5 Click is a compact add-on board representing a current-limiting solution. This board features the MIC2099, a current-limit power distribution switch from Microchip Technology. This Click board™ represents a programmable current limit solution with various protection features and fault indication, which operates from a 2.5V to 5.5V input voltage range. Also, the current limit is adjustable from 100mA up to 1.05A programmed through the MCP4561 digital potentiometer. This Click board™ is suitable for applications in portable equipment and condition monitoring or power supplies, protecting them in short circuits or other overload conditions.

Current Limit 5 Click is supported by a mikroSDK compliant library, which includes functions that simplify software development.

Current Limit 5 Click as its foundation uses the MIC2099, a current-limiting device with an adjustable overcurrent protection feature from Microchip Technology. The MIC2099 offers flexible protection boundaries for systems against input voltage ranging from 2.5V to 5.5V and limits the output load current to a programmed level (up to 1.05A). Additional safety features include thermal shutdown protection to prevent overheating, under-voltage lock-out, a soft start that prevents large current inrush, as well as automatic-on output after a fault condition.

The current-limit switch is virtually ubiquitous in system control and provides a safe means for regulating the current delivered to a load circuit. It allows the load current to increase to a programmed limit but no higher. Typically, the current limit is a function of the voltage across an external resistor, and this voltage serves as the reference for an internal current-limiting amplifier. By replacing the resistor with a digital potentiometer, you can easily program the current limit as performed on this Click board™. For this purpose, the digital potentiometer MCP4561 from Microchip Technology which communicates with the MCU via 2-Wire I2C serial interface, is used to set the resistance on the MIC2099 LIMIT pin, adjusting the current limit for the switch between 0.1A to 1.05A.

Current Limit 5 Click can be enabled or disabled through the EN pin routed to the CS pin of the mikroBUS™ socket; hence, offering a switch operation to turn ON/OFF power delivery to the connected load. It also provides a fault status indication signal, labeled as FLT and routed to the INT pin of the mikroBUS™ socket, alongside its LED indicator marked as FAULT to indicate different fault conditions such as current limit and thermal shutdown.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. It allows for both 3.3V and 5V capable MCUs to use the communication lines properly. Additionally, there is a possibility for the MIC2099 power supply selection via jumper labeled as VIN SEL to supply the MIC2099 from an external power supply VEXT terminal in the range from 2.5V to 5.5V or with VCC voltage levels from mikroBUS™ power rails. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

• Interface: I²C
• Compatibility: mikroBUS™
• Dimensions: 42.9 x 25.4mm
• Input Voltage: 3.3V or 5V, External
• Supply Voltage VCC: Min. 3.3V, Max. 5V
• External Supply Voltage VEXT: Min. 2.5V, Max. 5.5V
• Current Limit Range: Min. 0.1A, Max. 1.05A
• Operating Temperature Range: Min. -40°C, Typ. +25°C, Max. +85°C

• Schematic
• MCP4561 Datasheet
• MIC2099 Datasheet
• mikroSDK
• GitHub