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Questions tagged [74hc595]

Anything related to the 74HC595 integrated circuit. The 74HC595 is an 8 bit serial-input/parallel-output shift register with output latches and tri-state outputs.

Anything related to the 74HC595 integrated circuit.

The 74HC595 is an 8 bit serial-input/parallel-output shift register with output latches and tri-state outputs.

See Texas Instruments 74HC595 datasheet.

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How much current can my 74HC595 handle on each output pin?

So, I've been checking out the datasheet and I've gotten pretty confused... At the top it claims that 6mA drive at 5V but farther down in the absolute maximum ratings it says that the outputs can be up to 35mA. So, my question is, how much current…
TheNickmaster21
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How long between Arduino digital pin and IC?

My current project involves using 74HC595 shift registers to control an LED display, however the display could be up to 5 or so metres away from the Arduino board. The plan is to use some DB9/RS232 cables between a box with the Arduino, and an…
user1307
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Which SIPO chip is better, 74HC4094 or 74HC595 or something else?

I want to drive lots of LEDs in a spinning persistence-of-vision (POV) device. I need one output pin per LED, because matrix techniques don't work right in spinning POV devices. A serial-input, parallel-output (SIPO) chip is the best way to…
davidcary
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74HC595 - Initial output voltage

I've gone through the complete datasheet, searched SE and on google, but I cant seem to find this information: Whats the output Voltage of QA..QH just after power-up when G (Output enable) is pulled low, but no data have been clocked into the shift…
KarlKarlsom
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Multiple 74HC595 chained together won't light all LEDs

I'm new to Arduino - and electronics in general - and am having a frustrating problem with two serial-to-parallel 74HC595 chips trying to drive two 7-segment LED displays. The LEDs are both common cathode, and each LED input has its own 510 ohm…
Jono
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How to shift out 16 bits fast on arduino board

I'm coding a system that need to shift out 16 bits fast from a uint16_t variable to two paired 74HC595 shift registers. I'm running the code on an Arduino (atmega328@16Mhz) and the shiftOut in the Arduino is way too slow. The librarys digitalWrite…
tirithen
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POV globe speed questions

I am planning on creating a RGB LED POV globe only physically larger then that one. I am planning on using 64 RGB LEDs, requiring 3x pins per LED for a total of 192 outputs. Obviously I am going to need some shift registers. I have looked in to…
Steven Smethurst
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TIP120 Transistor + Solenoid Failing Randomly

I am using TIP120 transistors (controlled by 74HC595 shift registers) to control 12VDC, normally closed solenoid valves. Everything is working in short-time tests however when left overnight, some solenoids will open by themselves. The shift…
James G-J
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74HC595 Rows/Columns to drive LED matrix

Let's say we have one 74HC595 and we want to light 16 leds (common anode) connected as a 4x4 matrix exactly as in the following picture : So, 4 first outputs to controls 4 rows. The remaining 4 output to controls 4 columns. From what I understand…
Simon Ampleman
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Is there a way to control a 4 digit 7-segment display without a shift register?

I am trying to run a 4-digit 7-segment display using a RPi as a microcontroller (and there is a reason this is here and not on the RPi stack). However, all the tutorials i found require a 74HC595 shift register. I have one, but I want to simplify it…
DepthsDoes
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Why does a 74HC595N work in LED matrices?

I have checked a lot of LED matrices, and mostly a 74HC595N shift register is used. In some cases a TPIC595B like below. Example: Driving LED arrays with Arduino Circuit from above example: I understand that for sinking a TPIC is needed, because…
Michel Keijzers
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Arduino TLC5940 and 74HC595

I need to expand Arduino Uno output. After some search I have identified 74HC595 to extend my Digital output and TLC5940 for analog output. I'have also found how to connect them separately to Arduino Uno: This two setups share some pins, I've seen…
Nicola Pezzotti
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Why 74hc595 keep my light always on

I have a serial to parallel chip ( 74HC595-N ) which works well when I run the arduino script made for it. ( the current wiring work perfectly when I send data through the data pin ) But then I started to play around with other pins, leaving the…
FMaz008
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74HC595 Shift Register Latch Pin

I'm picking up a weird bug with my 74HC595 Shift Register's latch pin (Datasheet). What do I want to do? I'm essentially trying to visualise the shifting of the bits with the clock constantly running, and varying the serial input. I want to connect…
Hein Wessels
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Can I safely toggle the CS pin without sending any data?

Update: I've tried the solution I proposed in comments in practice (utilizing E pin on the 138 IC during changing target device) and it did indeed work. Read the whole thing if you want more details. simulate this circuit – Schematic created using…
Bartek Banachewicz
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