Designing a circuit for generating Asymmetric Rectangular Waveforms

Hello, Have a great day. We are startup company offering services in product development. We ahbve already did a lot of R&D work on TENS. we will deliver a design of fully working TENS that we have. Please feel free to contact us. Regards, Shahbaz.

Hi, I am a post graduate power electronics engineer and having very good industrial experience of 8+ years in R&D and project development. I am excellent high frequency transformers design, circuits design, multi-channel LED Drivers, Regulated power supplies design with universal input to DC output, Audio amplifier, drives design, Filters design for harmonic analysis and Power factor correction, SMPS, LED drivers, DC-DC, AC-DC converters design, PFC interleaved boost converter, Battery management system, Battery chargers, UPS design, sine wave Inverters, solar grid tie inverters, Solar battery chargers and street light systems design from few watts to KW range using Buck, Boost, and Buck –boost, Interleaved boost/buck, Fly back Push Pull and H-bridge inverters. I have work experience to design from few watts to KW range meeting all compliances like EMI/EMC and safety standards UL etc.

have worked on Transcutaneous electrical nerve stimulation. Probably you are interested in battery power unit controlled from computer through BT/BLE

Hello I have got your job posting “Designing a circuit for generating Asymmetric Rectangular Waveforms” and I am very much interested to work in your project. I am a circuit designer and have more than 5 years experience of working with the embedded systems(Arduino ,ARM processors ,PIC microcontrollers,All types of sensors and actuators). i have done tons of similar projects So, I think you’ll find, I have the skills you’re looking for. For more on my skills and successfully finished projects, please have a look on my Profile and Portfolio. I have all the components available here with me so i will develop a working prototype according to your specifications and then send you the code and schematics so things will work for sure. I am always available on Email and Skype. Please have a voice or video chat if necessary. I will be available more than 60 hours per week and able to start your project as soon as possible according to you. Thank you for your consideration, Best Regards, Haseeb Shafqat

For now I have sucessfully created a TENS device - so I'll need develop only BLE part - power part is ready and tested.

Thank you for reading this proposal . I'am an Electronics Engineer with professional experience of designing embedded systems with the process starting from circuit schematic design , MCU Algorithm development , finally leading to simulation and PCB designing . Following are the major projects that I have worked on: PIC18f452 based Data Acquisition Card for Three Phase AC Generators : Read real time generator parameters and display them on to the LCD and send it over the RF network using GSM SIM Comm Modem. (See portfolio). PIC18f458 based Electronic Load Controller for Micro Hydel Power Plant : Uses PI algorithm to ensure that the generated electrical frequency of the plant is steady. (See portfolio). Recently , I did a project that involved the design of PIC18 MCU based Assembly Line Controller for DC armature manufacturing . It had code , schematic , and a formal report Also , I have good experience in implementing transient and steady response modifiers , PD , PI , PID controllers . Your project yours wireless IoT product development , which I have relevant experience with . BLE transmitter and receiver will be installed at output and input side respectively . The output side will decode data received , which has the data related to amplitude , and frequency of the wave to be generated. Further my portfolio will reflect a perfect feedback score which shows a 100% client satisfaction . Let me know if you have any queries . Have a great day

Hi, Thanks for considering my BID. Please Note : The BID is for circuit design only. That is I would provide a schematic to you in PDF format and show you a simulation by a video of Proteus Simulation that it works. PCB Design, Firmware Development and Prototyping charges will require an extra fee and time. It will not cause burning sensation to the patient due to the asymmetric waveform. I have designed UltraSound, IFT, TENS and Muscle Stimulator all using Microchip PIC18F/dsPIC series microcontroller. I have seen major electrotherapy systems from different manufacturers in India and I am myself based in Kolkata. My design adheres to the finite principles of electrotherapy and not fake like most cheap products. I already have a Bluetooth application and yet to create an APP for Android which is well within my scope. I am currently working on a solid state ShortWave Diathermy unit that uses PLL frequency generation and some other techniques which does not require the Air core Inductor COILs or the Gang Capacitor. This is a long term project and I intend to finish it by March 2017. Once done I sell either the entire intellectual property signing NDA or give programmed ICs. I am not always available on Chat so might respond a bit later, then we can mutually agree suitable time to chat.

Hello, I am embedded systems designer with vast experience in bluetooth based design development and Android Bluetooth application development and can use Nordic nRF51822 SoC to build this project. regards, Ali

Thanks for providing us opportunity to place bid over the project and communicate with you. I am a serious bidder here and i have already worked on a similar project before and can deliver as u have mentioned .I have checked your requirements.i have right skills to work on this assignment Here we would like to bring in your notice that We are a team of professionals including experienced analysts, designers, project managers, developers and QA people having great expertise in web applications development mainly on core PHP, PHP with open sources (Joomla, Wordpress, Codeigniter, Cake PHP), .NET, Asp.NET, Vb.NET, HTML 5 etc. and mobile applications on ios and Android platform. We find our expertise, skills and capabilities are perfectly blends with your project requirements because we have already worked on many projects. I am ready to discuss with you Looking forward to hear from you. with best Regards

By the digital technology available an arbitrary waveform generation is not problem. My solution will based om microcontroller, DAC and reconstruction filter. A variable gain amplifier will provide the voltage swing according requirements. All parameters will be controlled via BTL connection. The host device will be not engaged in continuous generation of the same waveform data and will ony initialize and control the TENS device. Target cost for prototype (i can do it for you) will be under $100 @ 10 p. best - Val

we could develop such devices using AVR PIC or LPC21XX. even by using FPGA. we have development kits for all these devices. for high frequency we shall go for FPGA. frequecy and pulse width could be adjusted in program. fof amplitude adjustment u should use voltage dividers with a voltage follower circuit to get enough current..

I graduated from the IIT Kharagpur, Dept of Electronics and Communication. Right now I work as a circuit design engineer full time at Texas Instruments. I have 5 years of industrial experience. I have 1 US patent and multiple IEEE papers. I hope I can help you out.