Z axis accelerometer MMA1220D from Freescale

MMA1220D is Z axis MEMS accelerometer -8g – +8g. This sensor has capacitive sensor. The output signal is passed through 4 pole low pass filter. It also has internal self test capability. The main features: Integral signal conditioning; Linear output; Ratio metric performance; 4th order Bessel Filter to preserve pulse shape integrity; Calibrated self test; Detection of low voltage also clock monitor and EPROM Parity check status; Can survive high shocks. Where it can be used? It can be perfect tool for Vibration monitoring, control, bearing monitor, PC HDD protection, mouse and joystick, virtual reality, sport diagnostics. The datasheet can be found here: http://www.freescale.com I decided to run sample test of this sensor. For this I just made simple board where I soldered this sensor with SOIC16 package. According to datasheet I put RC filter on sensor output to minimize clock noise. There is schematic: And traced PCB: I used …

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PCB Etcher

After UV-80 vas built there was a thought about automatic PCB Etcher with autonomous Heater and bubble machine. This project is hanging in prefinished phase but it does a job. It was used to etch several PCB’s. As this etcher supposed to be used for making PCB’s using photoresitive technology, the controller supposed to control both = the heater of etching tank and heater of developer. As Sensors there are used AD7416 digital temperature sensors. I decided to publish this small project as this is not clear when it will be finished. When it will be, I will update this article. There is a little dirty drawing with dimensions: The dimensions are as follows 215x275x30 exterior. Inner volume is smaller as glass is 4mm thick. So overall volume is less than 1,2 liter. It is ideal volume to use one bag of ammonium persulphate or 250 grams of FeCl3. The …

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Ultraviolet light source UV-80 for PCB exposure

One of more advanced PCB manufacturing methods is exposing laminate copper boards covered by photo resistive layer through mask. Using UV light in manufacturing PCB’s has many benefits according to other methods: you can get thin tracks like 0.2mm. You couldn’t do this by using other home techniques like laser printers or hand artwork; other advantage is that this method gives clean image – smooth edges of PCB tracks. Little bit effort and you can compare results to commercial products. And pf course third benefit is speed and multiple replications of your boards by using the same mask. In this article is described the manufacturing of an automatic ultraviolet light source exposure box.   Parts for UV box Case with organic glass Panel UV lamps ballasts and starters Controller     Case Case is made of 5mm wood board wired with screws.   Making a control panel Control panel consists …

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Philips introduces advanced Hi-Speed USB microcontrollers

Royal Philips Electronics introduced the LPC2800 series – the industry’s most advanced ARM-based Hi-Speed USB microcontrollers on the market. The Philips LPC2800 is the first ARM7 MCU to deliver USB 2.0 device capabilities with maximum standard compliance and an on-chip Hi-Speed 480 Mbits/sec transceiver, and the first to enable single battery cell operation. These unique features allow embedded system design engineers to incorporate new capabilities into products such as PC peripherals, SD memory cards, smart card readers, and other USB battery-powered devices – all at a competitive price point. More at www.semiconductors.philips.com

ARM7 Development Tools

The development Software Keil for architecture ARM7 TDMI support the following devices ARM7: Atmel, Philips and Analog Devices, Sharp, OKI, ST Microelectronics. Instrument for ARM consist of the following parts: – CAARM Compiler/Assembler Kit Contains AARM Assembler, ARM Utilities, CARM Compiler, LARM Linker/Locator and the integrated medium of the development of Вµ.Vision IDE, which accomplishes complete control Compiler, Assembler; – PKARM – Professional Developer’.s Kit Includes all components CAARM plus of Вµ.Vision Debugger, which supports the complete simulation of devices and OS of the real time RTXA-Tiny; – DKARM Developer’s Kit – is included the integrated medium of the development of Вµ.Vision IDE and ВµVision Debugger; – Ar- ARM advanced Rtx- ARM the operating system of the real time Keil Rtx-ARM, which includes Flash File System and support TCP/IP Networking; – ULINK – adapter Usb-jtag for the connection of interface JTAG ARM7 to port USB of personal computer. Keil ARM …

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Healthy skin reflectance model

This pilot study is intended to investigate possibilities of skin nevus imaging using digital still image camera. The main objective is to develop method of dermatology images interpretation, which enables the looking on the skin lesions and nevus from the optical background of skin coloration. Kubelka-Munk calculation method for light transport and reflection from multilayered complex media is applied in modeling of light reflection spectra of skin. Calculation of model shows that red, green, blue and infrared colors lighting is satisfactory to access distribution of comparative estimates of the following skin parameters: volume fraction of melanin in epidermal layer, volume fraction of hemoglobin in dermal layer, presence of dermal melanin and thickness of papillary layer. Performance of image processing method on fourteen samples of images of common melanocytic nevi, dysphasic melanocytic nevi, Spitz nevus, thrombotic hemangioma and surrounding healthy skin were made. Skin spectral properties Understanding how light interacts with …

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Review on skin lesion imaging, analysis and automatic classification

The goal of any imaging methodology used in dermatology is to diagnose melanoma in early stages, because on it depends effectiveness of treatment. Investigations shows, that early diagnosis is more than 90% curable and late is less than 50% [1]. The diagnosis and successful treatment is often supplemented with permanent monitoring of suspicious skin lesions. Doctor’s diagnosis is reliable, but this procedure takes lots of time, efforts. These routines can be automated. It could save lots of doctor’s time and could help to diagnose more accurate. Besides using computerized means there are good opportunity to store information with diagnostic information in order to use it for further investigations or creation of new methods of diagnosis. Skin lesion imaging methods We found that there are number of various imaging methods of skin lesions [2]. The simplest visualisation method is photography. This method gives only top layer skin image. In order to …

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