Timer and Counter Modules
U1 CD4541 is a Timer with Long Duration Ability. This timer is started by a low pulse from earlier circuit, when the temperature goes above setpoint, a low state is at U2A inputs, this...
Category: Digital-Circuits
RS Latch Erroneously setting by Itself
I am having trouble preventing my rs latch from erroneously setting. The circuit is a voltage threshold detection circuit with a nand gate whose output is tied to a SR latch.
Decade Digital Counter Module – LED and LCD
I’m looking for a source of decade counters and wonder if you can help? I don’t want to build the counter, I want to buy a functioning counter module. Do you have source suggestions?...
Monostable Multivibrator CD4538
CD4538 is a dual Monostable Multivibrator. When you trigger the chip the output sends off one single pulse or one high-low event. Mixed Circuits Analog with Digital The T+ pin 4 of U1a is...
RS232 with Opto-Isolation
I had to once interface an high voltage circuit to PC, The uC had to communicate thru RS232–Comm port–Serial Port. Part of the 80C31 8051 SBC Even though i had isolation at the sensors...
Frequency Divider 74HCT4040
U1 7555 is a CMOS version of 555. The 555 here is in Astable Oscillator mode, C1 and C4 are decoupling capacitors 0.1uF value, ceramic disc. Mixed and Interface Circuits The output is around...
Usage of Schmitt trigger NAND Gates
I have a question about your “Long Duration Timer” circuit, del20017 found here ..Long Duration Timer Clock You have labeled U1 as a 4093. A 4093 is a NAND with schmitt trigger inputs, yet...
Dynamic Digital Tutors
Date: Wed, 30 May 2007 17:00:46 -0400 – Subject: 555 simulator Hello, I just found and had a chance to play with the 555 simulator over the internet. As I do a lot of...
