Questions tagged [ttl]
Transistor Transistor Logic. Logic circuits built from bipolar transistors and resistors.
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questions with no upvoted or accepted answers
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Fan out of TTL Circuit
In this image When calculating the fan out of the TTL circuit
the current in the TTL drive output is 16mA and is divided into the emitters of the load each emitter has 1.6mA because the fan out is 10.
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Switch between USB and Bluetooth module TTL
In my project I have an MCU that I want to communicate with via 5V TTL serial. I have two methods of doing this in my circuit, USB via an FT232R (5V) and Bluetooth via an HC-05 module and level ...
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Turn on/off a LED using a D-FF and a transistor
I'm trying to control a LED using some microcontroller and I designed a circuit using a D-FF and a transistor to handle it. It looks like this:
So I can control when to turn it on or of by simply ...
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What is the shortest pulse a controller can count?
I want to count short LVTTL pulses (about 20-25 nanosecond.)
Right now, I use an Arduino with four IN74AC161N binary counters, but this solution has some Arduino limitations.
I count pulses, send the ...
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Custom HDMI-to-( TFT or LVDS ) decoder/driver
I am working on a custom-made handheld PCB based around a PI Compute Module 3+ and one of the hardest steps I have found is how to include an HDMI-to-50pin-TTL driver on my PCB to run an LCD TFT 7&...
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L298 distorts signal
I connected STM32 F334R8 microcontroller to L298 H-bridge. I made some measurements. The problem is output signal on L298 has quite slow slopes and is not as sharp as input signal. I do not understand ...
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RS232 to TTL converter problem
I have a RS232 to TTL Converter which has 4 pins Vcc, Tx, Rx, GND . I am trying to make a serial communication with my PC. I have a AVR development board and I have tested my program by connecting ...
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Latch circuit to cycle power in an ATX PSU
I'm designing a system powered by an ATX PSU. I'd like it to be able to be switched on and off by a momentary switch but also to be able to be turned off by another input.
The latch circuit is powered ...
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How to obtain the counting of TTL pulses from an FPGA?
I'm currently working on a project in which I need to program an FPGA in order to connect it to a photon detector, that generates a TTL pulse when detecting a photon; I need to count this pulses, ...
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How to double a single TTL to link to 2 independent TTL terminal
I am working on a project that needs multiple serial connection between mcu sensors .
In order to send data by ttl serial from 1 mcu to 2 other mcu and reverse...
What is the best way to achieve this ...
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Confusion In Fanout of Logic Circuit and Transistor
Fanout:-Maximum Gate we connect to output of any Logic gate.
so there is limited number of gate we connect the output of Logic Gate.hence there is some minimum condition required for operation of ...
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Connecting RS232 GPS Board to Raspberry Pi
I purchased a NEO-6M GPS board to connect to my Raspberry Pi, and when I bought it I didn't realize that it was meant for RS-232 communication instead of UART TTL (which I believe is what the ...
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TTL in an RF switch
I am hoping to find help on how to properly connect supply voltage to my switch assembly in order to actuate. My switch has input requirement of +15, -15, GND, and +5V. Also, the 5v logic inputs. ...
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LTspice - how to simulate real TTL gates?
I am trying to make simpler more general questions that might have more generally useful answers.
If you build a mixed analog digital circuit then you need to have models of real TTL or CMOS gates ...
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Issues using a 74LS245 with Attiny85
I have a Raspberry Pi, a 74LS245, and an ATTiny85.
I connected the Pi to the Tiny through 1k resistors, and am able to use SPI to program it, no problem.
I have added a 74LS245 inbetween, to ...
