AVR DDS signal generator V1.0

Sometimes when tuning various electronic hardware, we need a simple signal generator with different waveform and frequency. One of the options is to by a professional with variable gain professional coating and many additional functions. But if you are a hobbyist, you might want to build one. This small project is dedicated to making one of those signal generators.  

Continue reading

Stimuli Generator for AVR Studio helps debugging programs in AVR Studio

Stimuli Generator for AVR Studio is a handy program that allows making stimuli files for AVR Studio. These files contain information on signals that can be used to affect AVR microcontroller pins virtually. With Stimuli Generator, you can emulate any interfacing like I2C, SPI, and others- this allows you to emulate real-world situations. The program’s working is simple: set target microcontroller (by default 8MHz), set measurement unit- microseconds or milliseconds. For instance, you want to send signals to Pin0 of PORTB. Target MCU -ATMega8, which runs at 4MHz. Set serial interface protocol, which is like start bit length – 60us, bit 0 – 20us, bit 1 – 40us. So, in this case, the step value would be 20us. Step value will depend on what variation on the duration of impulses.

Continue reading

Place electronics parts correctly on PCB

Let’s go through a few examples of how to place electronic parts correctly on the PCB board. SMD electronic parts, especially if the lead pitch is above 1 mm, then placement of leads has to be symmetrical on copper planes: If IC has a smaller lead pitch like 0.5 – 0.8mm, positioning by hand becomes harder. Sometimes it is recommended to use special glue to fix SMD parts before soldering. DIP electronic parts must be soldered as close to the PCB board as possible to make them stand stable and avoid heat resistance.

Continue reading

Drive dot LED matrix display using LPT port and driver IC

It is convenient to drive dot LED matrix displays using IC drivers of 5×7 dot LED matrices like MAX6952 and MAX6953. These two IC’s differ only by data interfaces: SPI for MAX6952 and I2C for MAX6953. In this article, you will see how these driver IC’s can be controlled by a computer using an LPT port. The program provided here works with almost all Windows versions: 95, 98, 98SE, ME, NT, 2000, and XP. The printer ports that can be used are LPT1 and LPT2. The program is called MAX6952, and it is programmed by using Visual Basic 5. To start this program, you will need a few standard VB run time libraries: MSVBVM50.DLL. The program uses a freeware driver of parallel port: DriverLINXTDLPortIO.DLL, responsible for hardware I/O in win32.dll and is not accessible by standard VB. Windows NT and Windows 2000/XP require drivers too. It is DLPortIO.SYS. Both drivers are owned by Scientific Software Tools, Inc. DriverLINXT is a registered trademark of Scientific Software Tools, Inc. First of all, installation on win98. Download file MAX6952-95.exe (793kB). This is a self-extracting archive that contains ReadMe.txt, ReadMeSST.txt, MAX6952.EXE, DLPortIO.DLL, and MSVBVM50.DLL. By default install directory is C: MAX6952. File MSVBVM50.DLL can…

Continue reading

New generation ICprog-AVR2.0 showed up

ICprog-AVR2.0 is a new generation USB AVR microcontroller programmer. The ICprog AVR is the smallest USB Programmer for Atmel AVR Microcontroller available on the market. The version ICprog AVR 2,0 programs with almost double programming speed as conventional programming adapters! The programmer is AVR910 compatible. Two versions of programmers are available: 6-Pin Version with standard AVR910 6-pin header 10-pin Version with KANDA interface

Continue reading

Endoscopy inspection in electronics-detect BGA defects

Endoscopy is known to be used in medicine, but it can also be used in other areas of industry like electronics. In big electronic industries where investments are huge, the requirements for quality are also big. In big industries, there is automatic testing using. This allows achieving maximum quality with minimal cost. In smaller industries, there is a requirement to inspect almost every product to avoid faults. One of the biggest problems that may occur is soldering errors, position errors, or other defects. For visual defect identification, endoscopy is often used. Endoscopy in electronics is some AOI (Automatic Optical Inspection), often used to check BGA pins. The endoscope usually consists of a light source directed by fibber glass and an optical sensor with variable focus. Changing focal length, it is possible to view about 50mm area while space between chip and board can be only 0.05mm. Information from the optical sensor can be sent to a computer for further processing. Comparing to the X-RAY method, optical inspection of electronic devices is cheaper.

Continue reading

Celsius converter to digital code from remote sensor

This circuit is originally published by Elana Lian and Chan Tran (Analog Devices). This simple single supply system enables to measure remote temperature with less than 1°C error in a range of 0 to 100°C: The circuit consists of the following parts: T1- low-cost AD590 temperature sensor; AD8541 – rail to rail amplifier; four resistors; potentiometer; and ADC AD7416. Use precision resistor RF for amplifier feedback to minimize scale factor.

Continue reading

Review on AVR serial and parallel microcontroller programmers

Its been a lot written about AVR microcontroller programmers. This article concludes most common programmers. The easiest programming method is Serial Downloading so-called ISP. This allows to program AVR microcontroller without removing it from the target board. Usually in such boards are a special ISP connector where you connect an external AVR ISP with standard 6 or 10 headers. AVR ISP usually connects to computers COM or LPT port. COM port has the advantage of the ability to use long cables while LPT is limited up to about 1 metter long. But in the other hand, using a COM port requires an additional complementary circuit to match the voltage levels, while the simplest LPT programmer doesn’t need any parts at all: But it is safer to use some kind of buffering circuit like 74HC244 to add some protection from port failure.

Continue reading

Few words about SMD-Surface Mount components

Today electronics is shifting to SMT (Surface Mount Technology) or SMD (Surface Mount Devices) area. DIP domination has left behind. They won’t vanish from the electronics industries as they are many areas and will be successfully used. But as electronic circuit complexity grows, demand for PCB miniaturization increases, there is no other way to use SMD technology to achieve these goals. Electronic hobbyists noticed that it is harder to find some particular electronic elements in DIP-packages. Many microcontroller types are released only in SMT packages like Atmega128– QFP64, LPC2000 microcontroller series in the LQFP package series. I don’t talk about bigger IC like AVR32 or FPGA, where BGA packages come with 672 connection balls.

Continue reading

Programmable logic devices

In a market, you can find a bunch of programmable logic devices – PLD. They can be small scale integrated – SSI, medium-scale integrated- MSI, mask programmed gate array – MPGA (MPGD – masked programmable logic devices). Now the most popular are FPGA (Field Programmable Gate Arrays). What is the difference between FPGA and MPGA? MPGA is hard-coded during manufacturing and cannot be erased or reprogrammed, while FPGA is programmable – usually EEPROM or SDRAM. Of course, there are other differences between FPGA and MPGA. One of them is speed. MPGA usually is faster as MPGA needs fewer elements to form a logic gate while FPGA needs additional elements to enable programmability – this adds additional resistances and capacitances in circuits. But today’s technology allows reaching significant speeds with FPGAs too.

Continue reading