Create dependable supply-solution for various battery-powered apps with MCP1811A and PIC18F57Q43

Single Cell Click is based on the MCP16251, a compact, high-efficiency, fixed frequency, synchronous step-up DC-DC converter from Microchip. This device provides an easy-to-use power supply solution for applications powered by one-cell, two-cell, or three-cell alkaline, NiCd, NiMH, one-cell Li-Ion, or Li-Polymer batteries. Low-voltage technology allows the regulator to start up without a high inrush current or output voltage overshoot from a low-voltage input. High efficiency is accomplished by integrating the low-resistance N-Channel boost switch and synchronous P-Channel switch. All compensation and protection circuitry are integrated to minimize external components. MCP16251 is paired with the MCP1811A device, a good choice for new ultra-long life LDO applications with high-current demands but require ultra-low power consumption during sleep periods. The MCP16251 on the Single Cell Click operates and consumes less than 14µA from the battery after Start-up while operating at no load. The device provides a true disconnect from input to output while in shutdown EN = LOW. While in shutdown, it consumes less than 0.6µA from the battery. The Single

Cell Click is designed to operate with a wide input voltage range down to 0.35V, accommodating many input sources. When considering a primary power solution for a design, the battery type and load current needs must be carefully selected. The MCP16251 start-up voltage is typically 0.82V at 1mA load, but this does not act as a UVLO start-up threshold. The device drains current to bias its internal circuitry before the 0.82V input. It can't start up or operate well with high-impedance sources because its voltage varies from zero to over 0.82V (i.e., energy harvesting). Start-up voltage is the point where the device starts switching in a closed loop, and the output is regulated and depends on load and temperature. Batteries are available in a variety of sizes and chemistries and can support a variety of drain rates. No matter the chemistry, most batteries have several things in common. They should not be drained below their specified FEP (Functional End Point or Cut-Off Voltage). Below this point, if the battery has a load applied, there will not be enough energy to deliver power because all usable capacity is used. For an

alkaline cell, FEP is 0.9V or 0.8V. Using the alkaline cell below the FEP will increase the risk of leakage. There is an exception for alkaline batteries: if the battery voltage is strictly monitored, it can only be drained down to 0.5V in one-cell applications. The FEP value is usually 1.0V – 1.1V for a rechargeable NiMH cell. Another situation is powering a boost circuit from one rechargeable cell like NiMH or NiCd. These applications need an external MCU to monitor the cell voltage or a separate UVLO circuit to prevent deep discharging, which results in permanent cell damage. In a multi-cell powered application (e.g., 2.4V typ. from two NiMH cells), deep discharging will result in a reverse polarity charging of one of the cells due to the unbalanced cell voltages, thus damaging the respective cell. This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.

PIC18F57Q43 Curiosity Nano evaluation kit is a cutting-edge hardware platform designed to evaluate microcontrollers within the PIC18-Q43 family. Central to its design is the inclusion of the powerful PIC18F57Q43 microcontroller (MCU), offering advanced functionalities and robust performance. Key features of this evaluation kit include a yellow user LED and a responsive

mechanical user switch, providing seamless interaction and testing. The provision for a 32.768kHz crystal footprint ensures precision timing capabilities. With an onboard debugger boasting a green power and status LED, programming and debugging become intuitive and efficient. Further enhancing its utility is the Virtual serial port (CDC) and a debug GPIO channel (DGI

GPIO), offering extensive connectivity options. Powered via USB, this kit boasts an adjustable target voltage feature facilitated by the MIC5353 LDO regulator, ensuring stable operation with an output voltage ranging from 1.8V to 5.1V, with a maximum output current of 500mA, subject to ambient temperature and voltage constraints.