Tag Archives: MCP1525

DIY USB Line Power Meter Stick

DIY-USB-Line-Power-Meter-Stick-Connected-to-Laptop-620x503

a new project is published on electro-labs.com, check it out:

Another DIY project designed with FabStream’s SoloPCB tool is ready to be shared with Electro-Labs community. This is an USB stick which measures the supply voltage of the USB port and current drawn by the device connected to the port over the stick. Then it calculates the power consumption of the device and displays the whole information with the help of the small OLED display on the board. The stick itself is also powered from the USB port.

The board is built around an Atmel ATMEGA328 microcontroller. To make the circuit as small as possible, the MCU is used in minimal configuration. Internal 8MHz oscillator is used. The voltage and the current are measured by the internal 10 bit ADC. To make the measurements more accurate, an external 2.5V voltage reference IC, Microchip MCP1525 is included. The current is converted to voltage on a 0.01R sense resistor and precisely amplified by LT6106 before read. The stick can measure up to 2.5A. Since the OLED display requires 3.3V supply voltage, L78L33ACUTR linear voltage regulator is used.

DIY USB Line Power Meter Stick – [Link]

Revised version of LM35 based digital temperature meter

embedded-lab.com writes:

This is a revised version of my LM35 based digital thermometer project that I posted last year. Although it is one of the simplest projects, it is very popular among newbies who are just starting to learn microcontrollers. There was a little flaw in the original project as pointed by some readers. I was using a 1.2 V reference for A/D conversion with PIC16F688 microcontroller. However, the PIC16F688 datasheet says Vref should be equal to or higher than 2.2 V to ensure 1 LSB accuracy of A/D conversion. Here, I am rewriting the same project but this time I am using a MCP1525 IC to generate a precise 2.5 V reference for A/D conversion. This will improve the accuracy of temperature measurements.

Revised version of LM35 based digital temperature meter – [Link]