A shift register is a cascade of flip flops, sharing the same clock, in which the output of each flip-flop is connected to the "data" input of the next flip-flop in the chain, resulting in a circuit that shifts by one position the "bit array" stored in it

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3answers
160 views

Turning off IC's when not used in battery powered circuit

I'm building a small battery powered device which contains an ATTiny85 micro controller, a dual common anode 7 segment display and 2x595 shift registers to drive the 7 segment display. The device ...
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2answers
66 views

How to extends Arduino Mega to 250 I/O pin

the title actually quite sums up my question, How to extends Arduino Mega to 250 I/O pin ? I will use it to drive 250 12 V relays (if a direct ic/chip that are 12V capable (max 50 mA per pin will be ...
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2answers
79 views

barrel shifter using multiplexer: how to go about it

I am trying to under stand how to build a barrel shifter using multiplexers. I understand how the barrel shifter works but I don't get how you decide the number of multiplexers to use, and how the ...
0
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3answers
50 views

Choosing decoupling cap for M74HC595B1R shift register

I want to use a bunch of cascaded M74HC595B1R shift registers in my project. VCC will be 5V, clock frequency 8-10 MHz. Outputs of these registers will be driving gates of 2N7000 N-MOSFETS if that ...
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3answers
58 views

Connecting 74HC165 to 74HC595

This is a rather noob and potentially silly question. I am planning to allow the user to randomly connect the 8 output pins of the 74HC595 to any of the 8 input pins of the 74HC165 shift out and shift ...
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1answer
54 views

Is there an IC that works like a queue for binary, serial data (like a shift register)?

Is there an IC that works like a queue for binary, serial data? I have searched a few sites for an IC like this, but I have no idea what the name of this IC would be. Here is a basic description of ...
0
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1answer
74 views

Mux and Adder going into Infinite Loop

I have been trying to learn verilog with help of a project. The mix that takes adder output as input and gives input to adder as per the control signal is going into an infinite loop, but it should ...
0
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1answer
53 views

How to Insert values in 2d array in verilog

I wrote a verilog code for Circular Shift register using a 2-d array, but can't seem to insert values in the array. Here is my code ...
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2answers
51 views

Parallel input to serial output

I have been learning a bit about electronics. In particular I have been playing with the shift register 74HC595. Here I understand how bits are moved into the register serially, that is one bit at the ...
-1
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1answer
57 views

VHDL blink leds for changing bits in vector signal

Suppose there's two SDT_LOGIC_VECTOR signals A_READ and A_OUT, both 8 bits wide. A_READ is updated by some process at random intervals. A_OUT is connected to 8 LED's. I want to blink a LED for each ...
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0answers
50 views

VHDL optimization: shift register with reconfigurable outputs

I am looking for some advice to optimize my beginner's design. Logic needs to be implemented on a CPLD that is able to : receive data from 4 parallel in/serial out shift registers through 4 serial ...
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3answers
91 views

Is there an IC that can shift-in, store and shift-out serial data [closed]

I want to storing serial data from an Arduino, and make it available for a second Arduino to read. Is there an IC that can receive serial data, store it, and send it out when needed? One solution ...
1
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3answers
76 views

Can I connect multiple SN74HC595 shift registers separately (without daisy chaining them) to the same Arduino?

I'm sort of a newbie to this whole idea of shift registers and the Arduino shift register handling library. I've found many demonstrations online, where shift registers are daisy chained. But I need ...
0
votes
1answer
118 views

Running LED dot matrix using shift registers

So as the title suggests, I'm using 3 shift registers (74595) to run a dual colour LED dot matrix display by daisy-chaining them (I believe that's the term). I haven't got to the coding bit yet, but ...
2
votes
1answer
134 views

shift register problem in VHDL

I'm designing a 56 bit shift register to store the bits coming in. In my system, 8 bit data is keep coming in from a generator and I need to output the maximum value detected with 3 bytes either side ...
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1answer
179 views

Why is the 74hc595 shift register causing a few pins to be lower voltage than others?

I've wired up two 74HC595s to a Photon from Particle. I followed this guide here for Arduino in how I wired it. The only place I deviated is to not put a capacitor on the latch pin. It all appears to ...
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4answers
107 views

Can this shift-register circuit be simplified?

I've created a circuit using a shift register to drive a 7-segment display which is all controlled by an Arduino Uno. The circuit appears to work fine, I have a sketch running which simply counts ...
0
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1answer
88 views

Controlling 4x4 LED matrix with Huzzah Feather and 20-pin shift register

I have a Huzzah Feather and a 20-pin shift register TPIC6B595N. I am trying to control a multiplexed 4x4 LED matrix which I have soldered appropriately. I am trying to figure out the proper way to ...
3
votes
4answers
267 views

Why would a designer choose to use two AND'ed input shift register such as the 74HC164?

Today I came across the 74HC164 8-bit serial-in/parallel-out shift register. Reading its datasheet, I realized that it has two serial inputs, instead of one like other shift registers, such as the ...
0
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1answer
60 views

What are the options of having multiple I/O pins and a constant duty cycle?

For some context, I want to create something like this. For now, until I change my chips (which I know I need to do as a plan to use a lower voltage Vcc2) I'm using the sn754410 h-bridge IC, 74HC595 ...
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1answer
288 views

Shift Registers - How does one pronounce QH'

In the datasheet for the 74HC595 shift register, pin 9 is labeled "QH'" (not to be confused with pin 7, labeled "QH" without the "'"). I understand that this pin outputs the current contents of the ...
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1answer
41 views

Misbehaving CD4021BE Shift-in

I have a CD4021BE set up very similarly to the Arduino ShiftIn Tutorial (the main difference being that I don't currently have 8 buttons so have just connected PI-5 to PI-7 to ground with a resistor, ...
0
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1answer
53 views

Shift-register circuit chronogram

Having this circuit and chronogram: I have to complete the chronogram for Z1 and Z2. This is what I have done: I'm a bit confused about ini being 1... I thought that it meant that Z2 would ...
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1answer
65 views

PISO Shift Register using 74LS166

I'been doing a PISO shift register using a 74LS166, but I get no results, I don't know what is happening. Here is the top view and my approach. In my approach: BLUE wire = Clear PURPLE(MARRON) = ...
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1answer
102 views

How to isolate the microcontroller from power source?

I'm fairly inexperienced in electrical engineer so forgive the simple question. Using a microcontroller (Netduino) and two 8bit shift register (serial in, parallel out) I'm controlling 16 LEDs. The ...
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0answers
46 views

Where am I going wrong with my datflow diagram?

I am trying to make a dataflow diagram of this: Here is what I have so far but it doesn't seem right: Where am I going wrong with my dataflow diagram?
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1answer
177 views

Do registers have a multiplexer?

We are learning about general purpose shift registers. My professor draws them with like multiplexers connected to the D's of each flip flop. So in an example of a register with a 4 bit input and ...
2
votes
1answer
192 views

ADC using MCP3008 on FPGA -

I am at the moment trying to use MCP3008 as an ADC, but for some reason it doesn't convert the output correctly. (A beginner project). I provide it with an 3.3 V = vref = Vdd = ch0 But my output ...
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1answer
245 views

What is the difference between 74HC595N and 74HC595B1R shift registers?

They seem pretty the same, but B1R version is almost twice cheaper (at least in my country, and I don't know what are the manufacturers).
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1answer
134 views

Bad design of shift register

I've tried to make a shift register by myself. The syntax is correct but i'm not sure if this could a good design... i commented the statements that concern me... ...
0
votes
1answer
110 views

Can´t get 8-bit shift register working (CD4014BE)

I can't seem to get my 8-bit shift register working. It's the CD4014BE. The datasheet can be found here. I've confirmed that the clock (pin 2) is ticking and the input (pin 4) is continuously ...
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2answers
45 views

What does it mean by “storage clock” of a shift register?

I read the data sheet of a shift register and I saw some tutorials on the internet. I can use all pins of my new shift register except pin 12. because I still don't understand what is the meaning of ...
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1answer
196 views

Can you calculate clock to output delay from setup time, hold time and the propagation delay of wires?

"minimum tCO = <shortest clock to source register delay> + <micro clock to output delay> + <shortest register to pin delay>" is what I found on this ...
2
votes
1answer
131 views

AVR SPI shift register not clocking

I'm trying to generate parallel output by writing serial data into a shift register (SN74HC595) via SPI on an ATMega328 (SPI master) running at 20MHz and SPI running at 10MHz. The bare minimum ...
0
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2answers
92 views

Simplest way to produce a lagging pulse (latch trigger) after receiving another pulse (clock trigger)?

I am teaching myself how to use a 74HC595 shift register, and am fairly new to proper digital circuit design. I ran into a question. I am using a simple circuit involving a few LEDs, a switch for ...
1
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1answer
102 views

Can the CMOS 4014b be used as a SIPO shift register?

I'm currently working on a school project that requires the use of an 8-bit shift register. I collected the components for the project on the last day of school rather hurriedly, and I picked the ...
-1
votes
1answer
40 views

VHDL - Wrong result changing MSB of R2 input

I'm implementing a shifter using a similar strategy of T2 shifter. My implementation is in structural way but I have a problem. My code of Shifter is: ...
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1answer
63 views

How to Separate 7 segment power supply

I'm trying to drive a multiplexing double digit 7 segment (5261AS) using Arduino and two shift registers (74595) I need to separate power supply for the 7 segment to avoid overloading current from the ...
1
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1answer
58 views

Is this a safe design for an input at a 74HCT165

I'm new to designing my own circuits so please be kind and tell me if I'm right with my thoughts or if I have errors in it. Thanks! The purpose of the 12V is to compensate the resistance of long ...
1
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2answers
2k views

How to get 3.3V from 2 AA batteries? [duplicate]

I would like to know if its possible to 'step up' the voltage from two AA batteries (3V for Alkaline and 2.4V for NiMH) to a stable 3.3V ? I need to find a good power source for a circuit that I'm ...
0
votes
1answer
159 views

Problem with 7-segment display: dimly lit when off

I'm driving two large seven-segment displays using two shift registers (74HC595). The displays have a forward voltage of 12V and a max forward current of 20mA. I'm feeding data and 5V of power to the ...
2
votes
1answer
128 views

shift registers/d flip-flop memory states

I know D flip-flops retain a certain logic level(memory) but when they output(i.e. shift) this retain memory do they loose it? for example: lets say I have 3 d flip-flops connected as a serial shift ...
0
votes
2answers
57 views

CD4015BC static shift register: technical specs question

Currently looking into the specifications of the CD4015BC static shift register, I came across a couple of specs for which I have some questions: 1) The clock rise and fall times should be below 15 ...
1
vote
1answer
264 views

Shift registers, understanding parallel-in serial-out

I have the 74hc597 parallel-in serial-out (PISO) shift register. The datasheet can be found here. I have a general idea about how serial-in shift registers (SIPO) work, but I'm having trouble ...
-1
votes
1answer
152 views

8-bit Serial I/O Parallel I/O Bi-Directional Shift Register [closed]

I am looking for a register that has as stated Serial In Parallel Out and Parallel In Serial Out modes and bi-directional shift functionality all in one IC. I want to use it with Arduino. Does ...
0
votes
3answers
708 views

shift register RGB led brightness

I'm currently using 74HC595 shift register to light leds. Recently I decided to start using RGB leds instead of simple 1-color leds. Which means that I now have to ...
1
vote
2answers
653 views

Driving two large 7-segment displays using Arduino and shift registers

I recently started a project in which I want to control two 7-segment LED displays using two shift registers (74HC595) and my Arduino. I thought I had the basic ideas mastered, but I ran into some ...
0
votes
2answers
111 views

Shift registers in series

If we have for example 3x16bit shift registers connected in series, can we clock 48 bits of data through one shift register at once and then latch all of them to output data registers, LATCH CLK and ...
2
votes
2answers
263 views

LED hub purpose?

What is the main purpose of LED hub, is it used only for RGB matrices to connect shift registers for every color or there are some other applications? I'm working with HUB75 and that is the reason ...
0
votes
1answer
66 views

Shift register on sync RS flip-flop

I am trying to build serial-in shift register (non cycled) based on synchronous RS flip-flop, but i'v got a problem with synchronization. My clock generator was configured to long on period and short ...