Texas Instruments 74LS Encoders, Decoders, Multiplexers & Demultiplexers are available at Mouser Electronics. Mouser offers inventory, pricing. 15 Apr 74LS CDIP − J. Tube. SNJ54LSJ. SNJ54LSJ. −55°C to °C. CFP − W. Tube. SNJ54LSW. SNJ54LSW. −55 C to C. The SN74LS and the SN74LS are Priority Encoders. They provide priority decoding of the inputs to ensure that only the highest order data line is.
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Since the the inputs to the 74LS are active 74ls148, you actually want the common lead of all the switches to go to ground, instead of VCC. That 74ls148, when using a chip like the LS you 74ls148 want to rearrange the connections as shown below and use pullup resistors to establish the high levels on the inputs to the chip.
Post as a guest Name. I repeated the entire process with 74ls148 74LS IC to make sure the first one was working. 74ls148
74LS – 8 to 3 Binary Priority Encoder
74LS148 – 8 to 3 Binary Priority Encoder
Post as a guest Name. I think you should include a bleeder resistor at 74ls148 to draw some 74ls148 current. Wildan Maulana Syahidillah 3 1 4. Sign up or log in Sign up using Google.
This will help 7l4s148 function as desired. Besides tying the common lead 74ls148 the switches to ground, I would also connect 4. Sign up using Facebook.
74ls148 up using Email and Password. I’d could really use a little help. I then tried using pull up resistors, the use and 74ls148 configuration of which is not entirely clear to 74ls148, which I think is the problem.
With your DIP switch connected as described you will need to provide a way for the inputs of the decoder chip to go low when the switch is off. To be honest, I didn’t 74ls148 know how to use the dip switches, but I get it now, 74ls148.
Motorola – datasheet pdf
I then tried connecting some inputs, along with their resistors, to the Ground. 74ls148 4, 12 35 Sign up using Facebook. Questions Tags Users Badges Unanswered. The 74LS you show is doing just the opposite of what he wants, the takes 3 inputs and expands it to 8, 74ls148 is taking 8 inputs 74ls148 encoding it 74ls148 3.
I read the question in dyslexic manner. But, 74ls148 you mean it could work just by tying the common lead of the switches to ground without needing any pull-up resistors? I’d still add the pull-ups though.
This way it will work for both types of chips. In 74ls148 case, in your example only 74ls148 A, B 74ls148 C should come from switches. The output still remained on a HIGH state, around 4.