Heart On-A-Chip Beats – Microbots put all organs on-a-chip


by R. Colin Johnson @ eetimes.com:

Living beating hearts on-a-chip were recently created from pluripotent stem cells discovered by 2010 Kyoto Prize Winner, Shinya Yamanaka. Bioengineers at the University of Berkeley aim to create all of the human organs on-a-chip then connect them with micro-fluidic channels to create a complete human-being on-a-wafer.

“We have learned how to derive almost any type of human tissue from skin stem cells as was first discovered by Yamanaka,” professor Kevin Healy told EE Times. “Our initial application is drug screening without having to use animals, but putting organs-on-a-chip using the stem cells of the patient could help with genetic diseases as well.”

Heart On-A-Chip Beats – Microbots put all organs on-a-chip – [Link]

Comparing the NE555 Timer and LM386 Amplifier as Inductorless DC-DC Converters


by Petre Petrov @ electronicdesign.com:

The bipolar NE555 timer IC is widely used in inductorless dc-dc converters, most frequently in doubling and inverting converters. However, another very popular IC, the LM386 audio amplifier, may be a better solution in this application. Note that the results also depend on the specific manufacturer of these multisourced ICs and on the quality of the related components. (We will use only Schottky diodes, to reduce the voltage losses to the minimum.)

Comparing the NE555 Timer and LM386 Amplifier as Inductorless DC-DC Converters – [Link]

120A Solar BMS charger LiFePO4,Li-ion OffGrid,RV with WiFi


The NEW Solar BMS charger for LiFePO4 or any other Li-ion battery and used for OffGrid House, RV or boats, with wireless datalogging.

 Solar BMS (Solar Battery Management System)is a solar charge controller designed to replace the Lead Acid solar charge controllers most people use today in Offgrid, RV, Boats and multiple other applications with 12V and 24V systems. Solar BMS can be used with 3 up to 8 Lithium cells (any type) or supercapacitors. The new SBMS100 will have multiple improvements over the first generation SBMS4080 see further for details.

120A Solar BMS charger LiFePO4, Li-ion OffGrid,RV with WiFi – [Link]


LTC3899 – 60V Low IQ, Triple Output, Buck/Buck/Boost Synchronous Controller


The LTC®3899 is a high performance triple output (buck/ buck/boost) DC/DC switching regulator controller that drives all N-channel synchronous power MOSFET stages. The constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. The LTC3899 operates from a wide 4.5V to 60V input supply range. When biased from the output of the boost converter or another auxiliary supply, the LTC3899 can operate from an input supply as low as 2.2V after start-up.

LTC3899 – 60V Low IQ, Triple Output, Buck/Buck/Boost Synchronous Controller – [Link]

Dynamic Voltage Scaling with a Dual LDO


This application details how a dual-channel LDO may be used to provide a dynamic voltage scaling output. This function is useful when powering microcontrollers that have a wide operating voltage range: it is advantageous to lower the operating voltage of the MCU in order to achieve lower power consumption (when possible).

The MSP430G2001, for example, has a supply voltage range that varies depending on the system frequency and programming modes. As an example, when the system frequency is 1MHz and flash memory programming is not required, the supply voltage range spans from 1.8V to 3.6V. However, if flash memory programming is required, the supply voltage range contracts to 2.2V to 3.6V.

Dynamic Voltage Scaling with a Dual LDO – [Link]

World’s first fully digital radio transmitter built purely from microprocessor technology


by Colin Jeffrey @ gizmag.com:

For the first time in history, a prototype radio has been created that is claimed to be completely digital, generating high-frequency radio waves purely through the use of integrated circuits and a set of patented algorithms without using conventional analog radio circuits in any way whatsoever. This breakthrough technology promises to vastly improve the wireless communications capabilities of everything from 5G mobile technology to the multitude devices aimed at supporting the Internet of Things (IoT).

World’s first fully digital radio transmitter built purely from microprocessor technology – [Link]

Sine wave oscillator using LM741


Sine wave oscillator using LM741, a project by A.M. Bhatt of EngineersGarage:

There are different kinds of Sine wave oscillators based on the components used or based on the output frequency that they generate
1. Based on components means if they produce oscillation using resistors (R) and capacitors (C) then they are called RC oscillators and if they use inductor (L) and capacitor (C) then they are termed as LC oscillators
2. Based on output frequency means if they generate frequency in audio range (20 Hz – 20 KHz) then they are Audio Frequency (AF) oscillators. If they generate frequency in low range (100 – 200 KHz) then they are called Low Frequency (LF) oscillators and last, if they generate frequency in high range (in MHz or GHz) then they are termed as High frequency (HF) or Radio Frequency (RF) oscillators.

I am presenting here two such sine-wave oscillators that uses RC components to generate oscillations and they can generate frequency in AF range as well as RF range. The two oscillators are
1. RC phase shift oscillator
2. Wien bridge oscillator


Sine wave oscillator using LM741 – [Link]



Determine the values of the node voltages va and vb for the circuit shown in the figure. The first node equation: the voltage source voltage is related to the node voltages by vb- va = 12  =>  vb = va + 12. To write the second node equation, we must decide what to do about the voltage source current.  KCL can be applied to the problem to generate the 2nd node equation : va/6 + vb/3 = -2. In summary, the node equations are vb – va = 12 and va/6 + vb/3 = -2. Solving the node equations gives va = 12 V; and vb = 0V.

Supernodes – [Link]

With the WIZ550WEB module you’re immediately on the web


New communication module WIZ550WEB offers interesting possibility how to get any device on the web.

To administrate devices through a web interface is simple, fast and comfortable. Also can be added, that it´s a solution that saves time and money and in a vast majority of cases it´s beneficial for a producer and also a customer. Besides common “network devices” for example for data acquisition (telemetry – when we want a device to send measured data), a network connectivity is still more used at devices, whose functionality is not dependent on a web connection. Usually here belong devices, where this “extra functionality” brings several advantages.

Example of such device can be for example a heating boiler, where a user can comfortably monitor its operation and change temperature and in case of a required service a producer can diagnostic the device remotely – without a costly personal inspection.

Novelty in this field is the WIZ550WEB module based on the W5500 chip (10/100 Mbps) from company Wiznet and the STM32F103RBT6 MCU. Hardwired core is highly stable and resistant to attacks. By means of the WIZ550WEB module you can use 16 digital I/O pins and 4 analogue inputs. It also supports serial configuration via AT commands.

The simplest way to start is to use a rich-featured development board Wiz550WEB-EVB with 8 output relays, 8 digital inputs with optocouplers (TLP290-4) and 4 analogue inputs (0-12V).

Detailed information will provide you documents Wiz550WEB_datasheet, Wiz550WEB_getting_started and Wiz550WEB_users_guide. Also useful are Wiz550WEB and EVB kitu schematics.

With the WIZ550WEB module you’re immediately on the web – [Link]

AM shortwave transmitter


Bring back the nostalgia with a tube transmitter! Are you interested in building this AM shortwave transmitter? Most parts used are still available, download circuit diagram for details. You can find more RF projects here: www.stationqrp.com

AM shortwave transmitter – [Link]