TTL：生存时间，主要用于三层数据的防环，TTL在IPv4包头中携带，共8个bit位，最大值255，每经过一个三层设备就减一，为零后丢弃该数据包。

Point of terminology: "TTL serial" is a severely over-broad term, " (point-to-point) asynchronous serial (at TTL levels)" seems to be what you're asking about. (Though that's still probably …

Aug 14, 2012 · TTL mean Transistor-Transistor-Logic and has its level for logical zero near 0V and for logical one near 5V. Often any 5V logic is called TTL, although most circuits nowadays …

Jun 22, 2023 · TTL requires that logic 1 input must be at least 2V, and TTL drivers are designed to guarantee that. That is far short of what this driver requires to register as logic 1.

Mar 8, 2024 · 此外，增量编码器的信号输出电平标准也是多样的，常见的有TTL、HTL、PNP和NPN等。 TTL和HTL是常见的电平标准，其中TTL为长线差分驱动，而HTL也称为推拉式或推 …

Mar 10, 2018 · I've been having some issues lately with the usage of 10k ohm resistors as pull down resistors for 74ls series chips. Most people seem to choose 10k resistors as their default …

Mar 21, 2018 · What is the difference of these two ttl nand gates? What is a totem pole, what does it do and what is it used for? When connecting multiple ttl logic gates together is it better …

Sep 11, 2020 · I keep coming back here searching for an RC-based negative edge detector for TTL levels, that generates a negative pulse on a falling edge. The only place I find this solution …

Dec 12, 2015 · TTL outputs have defined voltage levels for both low and high signals, but the high level can be as low as 2.4 V (depending on how much current the output must supply).

TTL integrated circuits assume unconnected inputs to be at logic 1 because the main requirement for driving a TTL input is to pull-down the level to near 0 V which takes about 1 mA per input. …