LOGIC GATE TESTER - Another nice work done by electronics(h) students of Rajdhani collge. keep it up... :) In this era of digital electronics the processors running at the speed of GHz, we want our command to be executed faithfully on any electronics system within a fraction of a second. There is no time for us to check a basic TTL and CMOS digital logic gate manually one by one for given sets of conditions (Truth Table) of that particular gate IC. The Logic gate tester is a programmable, easy to configurable and usable device. Sometime the main concern is to perform an experiment by building a complex circuit with the help of basic logic gate ICs not to find out which gate is functional or dysfunctional, so this device can save time and burden of checking gates of students and also ease the student to choose functional gate ICs. Arduino uno open source microcontroller board is being used in this invention which consists of atmel’s atmega 328p microcontroller and brain of the device . This microcontroller board consists of 14 digital I/O and 6 analog input(programmable to change Digital I/O) pins , which are used as various digital I/O for the gates .In any logic gate IC there are 14 pins in which 2 pins are reserved for the ground(0 V) and Vcc (+5 V) which are pin 7 and 14 connected directly to the microcontroller power rail simultaneously and depending on which gate such as NAND or NOR or NOT etc. a knob is rotated accordingly to that gate ,digital input logic(HIGH or LOW ) is fed to the input of the gates and logic output is taken from gate and again fed to the microcontroller unit which test the gate using the program which is preloaded in the flash memory of the microcontroller and if the is functional the LED glows . Currently this device supporting seven number of gates NAND (7400), NOR (7402), OR (7432), AND (7408), XOR (7486), XNOR (74266) and NOT (7404) and it can also test an LED. Software used: open-source Arduino environment. There are few steps to be followed to test an NAND gate IC Step 1: Place the IC in ZIP socket and rotate the knob so that it’s pointing to NAND gate. Step 2: Turn ON the power switch. Step 3: Observe the LEDs If all LEDs go ON all the means gate are functional and if some of the LED remains OFF that means that corresponding gate is dysfunctional .
Posted on: Mon, 29 Sep 2014 17:58:02 +0000