Questions tagged [ttl]
Transistor Transistor Logic. Logic circuits built from bipolar transistors and resistors.
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TTL to RS485 using MAX485 - Capacitor voltage requests
I need to implement a TTL to RS485 converter into an home made project and searching by Google I found this module with related schematics:
Could you help me by indicating the correct voltage for the ...
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Why does the 74LS08 see an input logic level even if the inputs are not connected?
I have an 74LS08 (AND gate.) I did not connect any inputs to the IC, but it gives me voltage at the outputs. Should I separate VSS?
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What is the correct maximum value for resistor R₁?
How do I calculate the maximum value of resistor R1 if the following values are known:
VDD = 5 V
inverter CMOS CD4069UB
IIL = IIH = 0 mA
VOH = 4.95 V
VOL = 0.5 V
IOH = IOL = 0.6 mA
VD = 1 V
maximum ...
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Communicating with 6 TTL devices that support the Modbus protocol
I am working on project using Hukseflux SR05-D2A2 thermal sensors. These sensors support Modbus communication through a TTL interface. The objective is to read the value at a specific address in the ...
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How do I know if it's RS232 levels or TTL levels
I have a random device: GT MEDIA V8 Finder Pro. I would like to communicate over its console port.
Here are some pictures of its mainboard. Here is the area around the console connector:
I have no ...
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How to calculate the resistor values for the zener diode and the BJT base?
I try to convert ~12V signal from a car button (the input voltage can be from 10V to 14V) to a logic level signal for MCU, but the signal should to be inverted (1 = 0, 0 = 1).
Below is my schema, but ...
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Failsafe circuit for a bistable latching solenoid
I am new to embedded circuits and working on a problem with which I need help.
I am using ESP32 soc for controlling a bistable valve using DRV8833 driver module. Please refer to this link for valve ...
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Why do 74-series counters label their enable pins T and P?
A few 74-series counter ICs I’ve looked at have two enable pins, and they’re labeled “T” and “P” (for example, the 74LS161A, or 74ALS867A). The “T” input affects the ripple carry out, and the data ...
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Power supply for medium-scale 74HC TTL circuit
I've developed an 8-bit computer, in the same vein as Ben Eater's wonderful 8-bit computer series. It's based on a collection of 74HCxx-series ICs, and fits (in theory!) on a single PCB board. I'm ...
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Bare esp32 chip auto programming mode help
So I'm very much a newbie when it comes to using bare chips but since I'm trying to make a project which requires very small modules for wifi I'm stuck using a bare one. My question would be how to ...
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Simplest circuit to provide a 0 or 1 TTL signal to a device
Please excuse the naivity of this question, I am not an electrical engineer. I need a quick solution, and don't have time to ask our electrical engineer to help. A supplier will bring a device they ...
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Schottky TTL current calculator [closed]
I have a problem from university where I have to calculate the I ccl. I am a little bit confused because I don't know how to do it.
The problem says as well that Schottky TTL state is 0 logic (I think ...
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J-K flip-flops TTL to CMOS
The following uses 3 TTL 74SLS76N J-K flip-flops, which are active low:
However, I'm trying to figure out what the settings for the PR and CLR inputs would be using CMOS CD4027 J-K flip-flops. For ...
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Understanding cascasing of 74185
The 74185 is a binary-to-BCD converter. It is designed cleverly utilizing the fact that both 10 and 2^n are divisible by 2 once, thereby omitting processing of the LSB entirely. More interestingly ...
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ESP32 custom hardware connection to USB-UART converter
I'm designing custom hardware based on the ESP32. I'm using Adafruit's ESP32 Huzzah as a reference. In the Adafruit design, an onboard CP2104 USB-to-UART chip is used, but I will be programming the ...
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