Everytime we need to test a stepper motor controller we have to connect it to the parallel port of the computer or to a function generator to obtain the necessary pulses the realize the movements of the stepper.
This is a quicker method to check a controller integrity. Simply to make the life easier here is a square wave signals generator. A potentiometer or a trimmer regulates the pulse generation of the 12F675 microchip (a square wave, between 20 hz and 3khz). Ok, there are thousands of different ways to create a pulse generator, but we had a lot of microcontrollers.
12F675 pulse generator - [Link]
The ULN2003A 7-way (or ULN2803A 8-way) darlington driver is usually the go-to chip of choice when you need to switch any high current load from a microcontroller’s GPIO. It provides seven darlington driver stages to give low-side switching and even includes seven common-cathode clamp diodes to snub voltage spikes when high inductance loads are used. Texas instruments have recently introduced an alternative device which is said to be the industry’s first seven-channel, NMOS low-side driver chip.
The TPL7407L is a high-current NMOS transistor array. It contains seven NMOS transistors that feature high-voltage outputs also with built-in clamp diodes. The input stage is compatible with GPIO logic levels ranging from 1.8 to 5.0 V and the maximum rating of each NMOS channel is 600 mA. Several outputs can be paralleled if it is necessary to sink higher levels of load current. The TPL7407L’s key benefit is its improved power efficiency and lower leakage compared to bipolar darlington drivers.
Efficient NMOS Driver Array - [Link]
by Steve Taranovich @ www.edn.com:
Freescale Semiconductor introduced the MM9Z1J638, AEC-Q100 qualified intelligent battery sensors with three measurement channels, a 16/32-bit MCU and a CAN protocol module in one 7 x 7 mm 48-pin QFN package.
The market this product serves is quite diversified with 12 V lead acid batteries, 14 V Li-Ion batteries, Lead acid multi-batteries, HV battery junction box, Energy Storage Systems (ESS), Uninterrupted Power Systems (UPS) and industrial automation.
Today’s trends in the battery market include complex battery algorithms, higher communication data rates with the CAN bus, better safety for Li-Ion batteries and increased mission-critical dependence on energy availability.
Start-stop requirements, together with others such as regenerative braking and intelligent alternator control, are driving demand for more precise sensing of the battery’s state to provide early failure warnings.
Intelligent battery sensor for automotive and industrial - [Link]
By Jon Gabay @ digikey.com:
Copper-based connectivity has served us well for a long time and will continue to do so in applications where it is effective from a performance and cost perspective. For very-high speed and/or long-distance signaling, however, the material cost and physical signal limitations of using metallic conductors has driven eyes to other transport mechanisms.
Fiber optics is not new, and the telecom industry has pushed development and deployment of fiber-optic transceivers and links so that they now span the globe. Very few of our designs have had the need to traverse long distances at such high speeds. Even fewer of us have had deep enough pockets to set up vast high-speed networks. On the other hand, engineers now are finding that local requirements are pushing the limits of metallic interconnects.
Microcontrollers and Fiber Optics - [Link]
Development tools from 8051, PIC, AVR, to ARM, displays, peripherials and virtually all for a successful development can be found in the production portfolio of company Mikroelektronika.
On the beginning there was an idea to bring on the market a user friendly environment (SW and HW) for development of applications with microcontrollers. Success and a big interest for everything, what can make development easier induced a gradual enlargement of production portfolio of company Mikroelektronika. The result is, that today company Mikroelektronika belongs to the biggest producers of development boards for the most favorite platforms like PIC, dSPIC, PIC32, AVR, STM32, Tiva C, 8051. Mikroelektronika development tools are certified as „third party tools“ or „design partner“ by many world companies like Microchip, Atmel, Texas Instruments, STM, Cypress, NXP and other.
Very interesting on the Mikroelektronika products is a comprehensive portfolio is, what means that for a given platform we´ll find software (compiler for mikroC, mikroBasic and mikroPascal), programmer, various versions of development boards, display and various peripherials. It´s worth to mention, that there are really many add-on boards available, for example: GPS, GSM, audio&video, measuring, power-supply, communication, data storage, … Some products of company Mikroelektronika also support a new graphic platform FTDI EVE. A big value for development of graphic applications are SW VisualTFT-(MIKROE-1418) and GLCD.
Is Microelectronics also your profession? - [Link]
Dhananjay Gadre & Nidhi Sharma writes:
Microcontrollers, the heart of all modern electronic gadgets, are increasingly powered with sub-5V power supplies. This complicates the control of external loads powered by higher voltages. The reduced I/O supply voltage leads to increased complexity in handling high-side voltage switching. Figure 1 illustrates the conventional solution for controlling a 5V high-side switch, driven here by a 3.3V signal.
Zener level-shifter drives high-side switch - [Link]
By Jon Gabay:
To do something useful, a microcontroller (MCU) must be connected to other devices. This connection is made through input/output (I/O) pins. More times than not, these days pins are multifunctional and can connect to A/Ds, D/As, linear functions (such as op amps and comparators), voltage references, and more. So for the design engineer, protecting these I/Os against potentially damaging static charges and other similar threats is of high importance.
In establishing proper protection for an MCU, engineers are finding that characteristics they have depended on for years have suddenly become less effective and they are forced to revisit problems of the past. Why? Principally, as a result of market pressure to reduce the cost of their products, semiconductor manufacturers have combined a higher level of integration with continued shrinking of process geometry, making die sizes smaller. As a result, implementing the necessary transient immunity protection to prevent malfunction due to transients on power and signal lines has become increasingly difficult.
Protecting MCU I/O Lines from ESD and Other Transients - [Link]
by Benabadji Noureddine:
This Design Idea demonstrates a new method of driving six LEDs with only two I/O lines from a microcontroller, and so is particularly suitable for any pin-limited chip. It uses a pair of I/O lines combined with a pair of complementary bipolar transistors. More than one LED can appear to be lit by multiplexing.
Two PIC pins drive six LEDs - [Link]
by Danny Mavromatis:
There are a lot of little details you need to think about when taking a project from PoC (proof-of-concept) to production. Most projects today have some form of onboard microprocessor and require you to flash your custom bootloader and/or program code onto it at some point. There are many ways this can be accomplished but the most common method is using an ICP (in-circuit programmer) connected to a 6-pin ICP header somewhere on the PCB. [...]
Tag-Connect! I can’t remember exactly how I found out about this neat little connector, but I’ve been using it for a while and it’s actually very useful in a production environment. They provide the footprint for many of the popular PCB design programs so placing it is very straight forward. Pretty much just swap out the traditional header for the new tiny Tag-Connect version and you’re pretty much done.
Tag-Connect: The ICP Connector That Saves PCB Space & Cost Less - [Link]