Chip-scale atomic clocks bring accuracy and stability to portable applications


Microsemi released a chip scale atomic clock reference bringing stability and accuracy to portable devices.

The Microsemi Quantum™ SA.45s CSAC is the world’s first commercially available chip scale atomic clock, providing the accuracy and stability of atomic clock technology while achieving true breakthroughs in reduced size, weight and power consumption.

The Quantum SA.45s CSAC produces two outputs, a 10MHz square wave and 1PPS, both in a CMOS 0V to 3.3V format. It also accepts a 1PPS input for synchronization and provides an RS-232 interface for monitoring and control.

Chip-scale atomic clocks bring accuracy and stability to portable applications – [Link]

WaRP7 – A New Platform For IOT And Wearable Technology Applications

“WaRP7” is a new platform which increases developer’s opportunity to innovate and bring new products to the market by smoothing and speed up the development process of IoT applications and wearable technologies.


WaRP7 is a $85 platform designed by “Farnell element14”. It consists of a main board and a daughter card. The main board comes with a i.MX 7Solo applications processor from NXP and 8GB storage memory. WaRP7 supports WiFi, Bluetooth, USB-OTG, BLE, and NFC connections.

The processor is a member of i.MX 7Solo processors family and it is designed for devices that require high-performance processing with low-power requirements and a high degree of functional integration. It features an advanced implementation of the ARM® Cortex®-A7 core, as well as the ARM® Cortex®-M4 core.

Using the daughter card ‘WaRP7 IO Board’, prototyping will be fast thanks to the ability of using various expansion modules. It has a flexible design connected with various sensors to collect data, and a MikroBus™ expansion socket which opens users to over 200 Click Boards™ from MikroElektronika.

WaRP7 features the following sensors, located in the daughter card :

  • A high-precision barometer.
  • A six-axis sensor combining an industry-leading accelerometer and magnetometer.
  • A three- axis gyroscope.

Another key element provided in the WaRP7 platform is a MIPI CSI Camera.


WaRP7 Architecture
WaRP7 Architecture

About the OS of WaRP7, both Linux and Android can work on it based on NXP-standard BSPs without modifications.

WaRP7 is an open source platform, the source files including the PCB design files are available Here.

Farnell element14 tries to provide  a solution for most challenges faced in IoT and wearables market with the WaRP7 platform, such as battery life, connectivity, user experience. Some examples of its applications are: smart homes, smart cities, smart appliances, activity tracker, smart health, smart clothing and more.


WaRP7 development kit is available for about 85$ and contains WaRP7 CPU board ƒ, WaRP7 IO board and Lithium-Polymer battery.

Read this factsheet for more information.

Via: Element14

ESP8266 Wifi enabled 8×64 pixel LED matrix display


Raj @ build an ESP8266 based led matrix display. This matrix is a modification of his previous bluetooth version and uses an ESP8266 as a web server to setup the display message. No other microcontroller is used to control the display so things are kept simple and easy to build your own.

This project is a modification of my previous Bluetooth-enabled LED matrix display project, which used 8×64 monochromatic LED matrix (total 512 LEDs) for displaying scrolling text message. The original project used Bluetooth for display data transfer from a smartphone, but this one now uses Wifi. The display message is sent through web browser to a ESP8266 module that is configured as a web-server. No Arduino or any other microcontroller is used. ESP8266 alone works as a WiFi server and drives the MAX7219-based LED matrices.

ESP8266 Wifi enabled 8×64 pixel LED matrix display – [Link]

A very simple DIY solar-powered USB charger


Raj @ tipped us with his latest project. It’s a simple, but useful USB Solar powered charger able to charge a power bank or your smartphone.

Yesterday, I built a very simple DIY solar-powered USB charger for my TP-link 10400mAh USB Power Bank. All I needed was a 6V/3.5W solar panel and the TD1410-based 5V buck converter module. I bought both of them on Aliexpress for less than $8.

A very simple DIY solar-powered USB charger – [Link]

Air pressure sensors in smartphones


Dr. Thomas Block has a great article about air pressure measurement on smartphones and which benefits this may have.

Today’s smartphones utilize a wide array of accelerometers, gyroscopes and various other sensors in their designs. Relatively unknown is the barometric pressure sensor, which measures air pressure. These sensors are currently being integrated into premium-grade smartphones, but are also becoming more common in mainstream phones or wearables such as fitness trackers and Internet of Things (IoT) applications.

Air pressure sensors in smartphones – [Link]

Circuit provides cold-junction compensation


Mark Maddox @ has a design idea on cold-junction compensation using AD7708.

The accuracy of any circuit or system that uses a thermocouple to determine the temperature of a process is limited by the accuracy of the method used to perform cold-junction compensation. In a thermocouple measurement, two wires of dissimilar metal join together at the “hot,” or measurement, junction. The isothermal termination of the thermocouple wires provides a second “cold,” or reference, junction. The potential across the thermocouple is proportional to the temperature difference between the two junctions.

Circuit provides cold-junction compensation – [Link]

100Vin, 5W out regulator uses primary-side control


LT8303 is a monolithic flyback regulator in a TSOT-23 package that simplifies the design of isolated DC/DC converters. By sampling the isolated output voltage directly from the primary-side flyback waveform, the part requires no opto-isolator, LT1431 or third winding for regulation. by Graham Prophet @

The LT8303 operates over a 5.5V to 100V input voltage range, has a 0.45A/150V integrated DMOS power switch and delivers up to 5W, suiting it for a range of telecom, datacom, automotive, industrial, medical and military applications. The output voltage is set with one external resistor and the transformer turns ratio. Several off-the-shelf transformers are identified in the data sheet. The LT8303 operates in boundary mode, which is a variable frequency current mode control switching scheme, typically resulting in ±5% output voltage regulation over the full line, load and temperature range. Boundary mode enables the use of a smaller transformer compared to equivalent continuous conduction mode designs. The high level of integration and the use of low ripple Burst Mode operation result in a simple to use, low component count and high efficiency application solution for isolated power delivery.

100Vin, 5W out regulator uses primary-side control – [Link]

Low noise Mini Electret Microphone PreAmplifier


The single supply microphone pre-amplifier amplifies the output signal of an electret capsule microphone to audio line levels. An op amp is used as a trans-impedance amplifier to convert the output current from the microphone in to a signal level voltage. The circuit works with 9V so it is good choice for battery operated systems.


  • Supply 9V DC
  • Current Approx. 3mA
  • On Board Microphone
  • Very thin and narrow PCB

Low noise Mini Electret Microphone PreAmplifier – [Link]

Printable battery paves the way for custom-shape power sources

A new type of batteries called “Printable Solid-State (PRISS) Lithium-Ion Batteries” was designed by a group of researchers from the Ulsan National Institute of Science and Technology (UNIST, South Korea). The new battery is created from consecutive layers of printed composite materials.

Representation of the PRISS Battery production process
Representation of the PRISS Battery production process

With a simple stencil printing process followed by ultraviolet cross-linking, a solid-state composite electrolyte (SCE) layer and SCE matrix-embedded electrodes are consecutively printed on arbitrary objects of complex geometries, eventually leading to fully integrated PRISS batteries. Then the rheological properties of SCE paste and electrode slurry adjusted to get thixotropic fluid characteristics, along with well-designed core elements.

This technology yields many positive features, it eliminates the need for conventional microporous separator membranes and the extra processing steps of solvent drying and liquid-electrolyte injection.

With this new type of batteries, unlimited forms and sizes of batteries will be available for our various projects.

Source: Elektormagazine