# TTL gate characteristics

In case of BJT for example, the input characteristics can be described with $$\I_B=f(V_{BE})\$$ and output characteristics with $$\I_C=f(V_{CE})\$$.
How can the input and output characteristics be described in case of TTL gates?

• $I_C$ is a function of both $V_{CE}$ and $I_B$ in a BJT. More than just $V_{CE}$ alone. – Hearth Nov 23 '18 at 0:30
• Yes, that's true. – A6EE Nov 23 '18 at 0:42

## 1 Answer

You may model a TTL gate, at least the original low-power devices as

simulate this circuit – Schematic created using CircuitLab