Showing posts with label Digital-Circuits. Show all posts
Showing posts with label Digital-Circuits. Show all posts

Friday, January 02, 2015

Digital Electronics Interactive Tutors

These were tutors which i first made at around 1999, improved them many times, it must be bug free by now. Now i ported them to google gadgets too.

Tutorials on Digital Electronics

If you like JavaScript and CSS or want to look at some work i did, study delabs code and dapj code.

Digital Electronics Interactive Tutors

Both my Electronics Learning and Javascript Learning Have one thing in common, it started by building a Audio Music Player.
In Electronics Theory Section

Thursday, June 19, 2014

Digital Circuits - PDF Circuits - delabs

These circuits are based on CD40xx Chips and other. You can use 74HCT or any other series that is available. use one family for a particular project. These were used nearly two decades ago. Use it for learning, glue logic or to interface your uC designs to external devices. Do not make only Logic based designs like some below. It would be better to use a uC, CPLD or FPGA if you are building a complex gadget Basic Digital Circuits

Digital Circuits - PDF Circuits - delabs

Digital Circuits - delabs

LM331 is a Voltage-to-Frequency Converters and 74C926 is a 4 Digit Counter. The first part of the circuit converts the amplified DC analog value from a shunt to pulses. The Second counts the pulses and Displays it on a Seven segment LED display.

Digital Timers, Counters and Clocks
  • Sequential Timer CD40xx
  • Sequential Timer 7217
  • Six Digit preset counter CD4518
  • Analog timer CD4541
  • Quad Presettable Timers
  • Digital Comparator 74HC85
  • Sequential Timer/counter 7217 with RAM
  • CD4060 and CD4020 based long duration timer.
  • Digital Timer Clock With Preset using Thumbwheel switch.
  • 1 Hz or 1 pps crystal clock using CD4060 and 32768 Hz Crystal
Mixed and Interface Circuits
  • Optical Proximity Switch
  • Profile Controller
  • Toaster timer 555
  • Quad analog input switch logic
  • Optical switch for water tap using LM555 and LM567
  • Diff input DS8830 to TTL convertor
  • Phase lock loop using 4046
  • Am hour meter for battery chargers or electroplating equipment. 74C926

Saturday, June 14, 2014

Electronic Shift Monitor

The Security Guard duty monitor below, shown in eight circuits at Digital Circuits - 1 are examples of logic circuits, i have converted them from the DOS Orcad to Orcad 9 and corrected some errors a few years back.

Electronic Shift Monitor - delabs

These circuits can be used for looking at the logic blocks or to learn. This product was built and sold to some firms many years back. Now these designs are best done with a PIC or Atmel chip. Here is the user manual

Electronic Shift Monitor ESM9000

This circuit was done with CMOS CD40xx type of ICs. A RAM was used to store the Day/Time LED Status.

This was custom made for a bank, it was to monitor the Alertness of the Security Guard. Periodically the Unit will Buzz and Flash and the Security Guard has to press a  Big Button to indicate he is awake, alert, agile and around the Unit.

In the Morning the Bank Manager will see the Security Status LEDs. All Green means fine, few Red LEDs means the Guard was sleeping or gone away from some times. All Red means Security Guard is missing. :-)

Made quite some numbers but was not profitable and soon similar lower cost clones appeared.

Wednesday, May 14, 2014

Three Point Preset Counter

This is a prototype of a Preset Counter. It is built with ICM7217. The cabinet is ABS Plastic DIN 96-96. The Panel is Engraved on Acrylic. I don't remember for which application it was used. It has three thumbwheel settings, when the proximity switch counts upto the set-value, the corresponding relay turns ON, with a State Indicating LED on front panel.

Three Point Preset Counter

These can be configured sequentially or to work synchronously, this depends on what customer wants. Both modes may give the same result. In sequential operation, Some of these counters-timers may need to wait for an external trigger or feedback from a limit switch or another process like pressure alarm. Then more Input options may have to be provided.

Counters, timers, analog-process and its interconnectivity makes up the various process loops or chain-reactions in Machine control. The various types of sensors for measurement and feedback of analog and event parameters, monitor the mechanical system and communicate the data to the process instruments. The Actuators like Drives, Solenoids, Pumps, Valves and Heaters act in accordance to the commands of the control system. This regulates and manages the process or machine to deliver consistent and repeatable yield of the end product.

Read More here - Digital Timers, Counters and Clocks

Monday, May 12, 2014

Digital Timers Counters and Clocks

Timers and Counters along with Analog Process Controllers formed the front end of Industrial Automation. Even today automation systems and control panels use analog timers and electromechanical counters. These are Indispensable. Analog + Digital combination controllers came next which were little bigger and offered better stability. They had thumbwheel switches as user interface in place of potentiometers.

Digital Timers, Counters and Clocks

uP based Systems with chips like 8085 came after that, they consumed more power and were big in size. The coming of Cmos uC like 80C31 made Process Instrumentation Small and SMD made even 48 X 48 DIN sizes possible. Now Analog and uC based designs are used in different applications. Digital Hybrids and uP instruments are not used as they were Transient-Technology Methods.

Digital and Logic Circuits Basics

You can start learning digital circuits by learning the operation of logic gates, see an interactive gadget tutor Logic Gates.

Then you can test the basics with these tutor gadgets
Circuits FAQ Related to Digital Circuits

Saturday, April 10, 2010

Digital Tutor Gadgets with Canvas View

The Digital Electronic Interactive Tutors Gadgets, have a canvas view now. That means in iGoogle and Google Sites, you can set it to full size with a embedded schematic. The Normal view is also available unchanged.
Here is a Snapshot of a Live iGoogle Page showing a Digital Preset counter Gadget in Canvas view.
Other Gadgets are Logic Gates Tutor and Digital Timer

From Soldermans Basic Electronics