CMOS-Based Galvanic Digital Isolator

Galvanic isolation is a principle of isolating electrical systems wherein it blocks the DC current flow (i.e. there is no direct conduction path). Isolation is the ability to couple one circuit to another without the use of direct wire connections. This technique is commonly used in two or more electric circuits that must communicate, but their grounds are at different potentials. It is an effective method to prevent unwanted current from flowing two units sharing a conductor. Its purpose is for safety by preventing accidental currents from reaching ground through a person’s body. This design features Silicon Labs' SI8642 CMOS digital isolator, which is a low cost, high performance, low power, and reliable isolated circuit. Read more

RGB LCD Display Electromyography using Arduino + MyoWare Muscle Sensor

Measuring muscle activity that uses electric potential as an indication to know the health, and diagnose muscles to its present status is referred to as electromyography (EMG). Electromyography also assesses the condition of nerve cell (also called as motor neurons) that controls the muscles and can detect neuromuscular disorders. The reference design is a LCD display electromyography using arduino plus myoware muscle sensor from Adafruit. The reference design features the standard LCD 181 also from Adafruit Industries LLC with the use of I2C/SPI character LCD backpack. The design also uses the muscle sensor surface EMG electrodes. Read more

Electronic LED Candle

This reference design is a simple electronic LED candle that is well suited for birthday occasion. It acts like a real candle, which constantly flickers and changes its light intensity depending on the airflow. It has 9 LEDs, which blinks at random period and phase that can also be blown by the user as if it is a real candle. It specially uses the C&K’s PTS830GM140 tactile switch, a micro-miniature switch with low profile and high actuation forces designed for wearable electronics. It features extremely low start-up voltage and high output voltage accuracy. Read more

ATmega328P-PU + VS1053 Based MP3 Player

The MPEG-1 or MPEG-2 Audio Layer III (MP3) is an audio coding format used to shrink the size of a large audio file into a smaller one (about 8.33% of the original file size), without affecting its sound quality. It is the most popular audio format downloaded and played on most digital audio players. Digital audio players basically use a digital signal processor (DSP) and a digital-to-analog converter (DAC) to play an MP3 file. The DSP processes the MP3 data and sends it to the DAC to convert it into an analog signal that can be heard if inserted into an audio amplifier with a loudspeaker. Read more

Ultrasonic Rangefinder Using Arduino Uno and PmodMAXSONAR

The rangefinder is a device that measures distance from the observer to a target being measured. The device uses a sensor as the method of gathering measurements of distance, such as ultrasonic, laser, and radar. The circuit is a DIY rangefinder using a PmodMAXSONAR ultrasonic sensor, an Arduino UNO, and a 16x2 LCD module. The ultrasonic sensor has an effective detection range of 6in - 255in. It can detect objects within 1in up to 20ft away. The PmodMAXSONAR can send range data in three methods: UART, analog and PWM. Read more

Industrial Firewire Cable with FireWire 400 Color Camera

The manufacturing industry has different automation setup. Some of the setup uses electronic devices for quality assurance and actual status monitoring like cameras, sensor module, and other related devices. The firewire cable used in this design has IP67 degree of protection with 5 meters in length. In this design, it illustrate an automation setup with a firewire 400 color camera and 1654028 industrial firewire cable of Phoenix contact integrated to a pc unit with protective circuit. Read more

PM2.5/PM10 Particle Sensor for Air Quality Monitoring

Air pollution is one major problem that every individual is at risk. The pollutant, that contributes to these increases as industrialization and technology upgrade. Particulate matter or “PM” is the term being given to such particles like smoke, dust, dirt, and soot, which can be found in the air. The particulate matters can be dangerous depending on concentration and sizes. The sizes which considered can cause health risk are PM10 and PM2.5, which among the said particulate matter, PM2.5 (approximately 1/30th the average width of a human hair) is the most harmful PM for the reason that it can penetrate and lodge deeply to the lungs. The PM2.5/PM10 particle sensor for air quality monitoring reference design is an analog-front-end design, which can measure the particle concentration and sizes in the air. The design uses INA132, a low power single supply differential amplifier consisting a precision op-amp with a precision resistor network. It comes also with OPA2320 and OPA320, which is a new family of low-voltage CMOS op-amp that features a linear input stage with zero-crossover distortions that delivers excellent common mode rejection ratio (CMRR) of typically 114dB over the full input range. Read more

6A H-bridge DC Motor Controller

Nowadays, most of the motor driver circuits make use of the H-bridge configuration for it enables the voltage to be applied across a load in either direction. Hence, it allows DC motors to run forwards and backwards. This design utilizes IFX9201SG 6A H-bridge motor driver manufactured by Infineon Technologies. The output of this integrated circuit can be pulse width modulated at frequencies up to 20kHz that enables operation above the human sonic range by means of PWM/DIR control. While the signal at the direction input defines the direction of the DC motor, the PWM signal controls the duty cycle. Read more

Soldering Smoke/Fume Extractor

The process of joining electronic devices to a PCB or soldering is always performed not only by electronic engineers or technicians, but also by hobbyists. In soldering, lead is used as filler metal to join the pins of an electronic device to the PCB pads. When lead is heated during soldering, it produces toxic fumes that are hazardous to humans when inhaled. Excessive exposure to lead oxide fumes can result in lead poisoning. As suggested by Occupational Safety and Health Administration (OSHA) agency, there should be proper ventilation during soldering to avoid or minimize exposure to lead oxide fumes. Read More

10W Stereo Class D Amplifier

This reference design is a simple 10W stereo amplifier providing a class AB performance with class D efficiency. Its efficiency is more optimized when a 12Ω to 16Ω speakers are loaded. It has an efficiency of up to 88% with a low quiescent current which is 24mA. In addition, this device is short circuit and thermal load protected and its power consumption has been reduced to increase battery life.  Read more

BMD-200 Module for Bluetooth 4.1 LE

The Bluetooth Low Energy (BLE), also recognized as, Bluetooth Smart is a wireless technology based on the Bluetooth standard that consumes lesser power and be produced at a lower cost compared to the latter. It uses the same 2.4 GHz radio frequencies as Classic Bluetooth, which allows dual-mode devices to share a single radio antenna. Read more

High Precision Heat/Flow Meter

Maintaining the equipment at its top condition is one way to minimize cost of replacement and downtime during operation. Industrial motors are vital equipment in industrial plant that runs everyday and maintaining its condition using manual checking takes time and effort. The reference design being shown is a wireless motor monitor that remotely monitors the condition of motors. The main component MSP430FR5969 ultralow-power MCU is a mixed signal master controller that offers leading low power consumption, analog and digital integration, and easy to use interface that makes it suitable for wireless monitoring system. The MSP430FR5969 has the integration of Ferroelectric Random Access Memory (FRAM) that enables it to combine fast read and write access of DRAM with lower power consumption. The reference design also has the CC2650 SimpleLink Multistandard Wireless MCU, which is a cost-effective 2.4Ghz RF device that is ideal for interfacing sensors, and collecting data autonomously while the system is in sleep mode. The TPL5100 nano-power timer is the external timer that wakes up the main component every 16 seconds. The TPL5100 can trigger wakeups at longer sleeps interval and has the maximum wakeup time of 18 minutes. The reference design also has the BQ25570 Ultralow-Power Harvester and Battery PMIC, which harvests energy from any source 100mV and powered by a lithium-ion cell battery. Read more

Simple Switcher Power Module

The power modules are widely found in devices today, these are used in conversion of energy. The LMZ36002 is a synchronous buck power module that has a 2A DC-DC converter. It is capable of having a small footprint and a low profile design, while still able to adjust the key parameters to meet the required design. The designed circuit is an evaluation module for the LMZ36002, so it would have an easy to use platform in showing the correct usage and the performance of the device. It has a wide output voltage that can be adjusted from 2.5V to 7.5V. The switching frequency also can be adjusted from 200kHz to 1MHz. Read more

IO-Link Device Transceiver

The IO-Link is a compliant of International Electrotechnical Commission (IEC 61131-9) standard. It is the standard for single-drop digital communication interface for small sensors and actuators. Furthermore, IO-link is a 24-V communications interface that allows smart sensors and actuators to exchange advanced configuration, status and diagnostics information using a powerful, yet simple protocol. It specifies point-to-point communication over a maximum distance of 20m using standard M5/M8/M12 connectors and 3/4/5 wire cables. The IO-Link masters provide communication over standard fieldbuses, such as Ethernet, RS485, etc., with any IO-Link device (smart sensor or actuator). Each master port provides both power and data over a single cable to each device. Read more

Battery Fuel Gauge

This reference design is a typical application for the bq28z610 Battery Fuel Gauge device. It is a 1 to 2 series Li-Ion/Li Polymer battery pack and protection solution, enabling independent charger control and cell balancing. The device provides a fully integrated pack-based solution with a flash programmable custom Reduced Instruction-Set CPU (RISC), safety protection, and authentication for 1- to 2-series cell Li-Ion and Li-Polymer battery packs. It also measures cell voltage and current simultaneously, and also measures temperature to calculate the information related to remaining capacity, full charge capacity, state-of-health, and other gauging parameters. Read more

Heat-Shrink Fabric for Industrial Wires

The manufacturing industries are used to have different types of motor in the operation. The motor plays an important role in the process because it provides convenience to operators. Majority of these motors used in the process are electrically powered, which some of these requires 3-phase supply or 2 single phase supply. These motor supplies are used to be in a control box that handle centralised splicings and connection of the electric motors. The connections of these motors are prone to mechanical strain due to the environmental condition inside the industry. This design features shrinkable fabric for wire protection. Read more

30W Stereo Audio Amplifier with Clipping Protection

This reference design features a 30W stereo audio amplifier that employs a motorized slide potentiometer to provide clipping protection. The PSM60-081A-103B2 is a half-watt, 10kΩ, 60mm, motorized slide potentiometer. It provides two built-in 10kΩ variable resistors labeled as line track and servo track. The line track variable resistor can be used for other purpose, while the servo track variable resistor can be used for tracking the position of the potentiometer lever. The built-in DC motor controls or adjusts the position of the potentiometer lever as well as the resistance of the line track and the servo track variable resistors. Read more

Dual Mode Battery Charger Circuit Using Adjustable Positive-Voltage Regulator

This dual mode battery charger is a simple electronic device that features the two essential modes of a battery charger. It has both the constant voltage and constant current characteristics which both prevents overcharging in batteries. The device specifically uses the Texas Instruments’ LM317L, an adjustable, 3 terminal, positive voltage regulator capable of supplying 100mA over an output voltage range of 1.25V to 32V. It is easy to use and requires only two external resistors to set the output voltage. Read more

FLORA as Wearable Pedometer

One of the devices used to monitor the progress of an exercise is the pedometer. This device is used to measure steps taken by an individual and determine the speed, distance and even calories burned to motivate them in getting fit. Present designs available in the market today uses accelerometer compared to the mechanical devices used in the early designs. This design uses the Flora v2 platform from Adafruit as the host controller for the system. It is built around the Atmega32u4 chip, which has built-in USB support. Read more

Ultra-low Power Multi-sensor Data Logger with NFC Interface

The cold chain monitoring is the process of ensuring a certain product temperature to remain constant upon shipping and distribution. The ultra-low power multi-sensor data logger with NFC interface reference design integrates multiple sensors for cold chain monitoring. The board features wireless communication through RF430CL330H dynamic near field communication (NFC) interface transponder. The TMP112 device is a digital temperature sensor ideal for NTC/PTC replacement and has an accuracy of ±0.5°C. The OPT3001 is an ambient light sensor that measures the intensity of visible light. For humidity measurement, the HDC1000 is a digital humidity sensor with integrated temperature sensor. The board also comes with MSP430 mixed-signal microcontroller. Read more