TTL TRANSISTOR DIAGRAM AND GATE SERIES

These are used in circuits where various power sources are available to perform the similar action.The main applications of OR logic gate are: Sometimes there might time delay between input and output.

It has limited functional voltage values.

Here, multiple signals can be connected to output which has no impact on the other results.

This gate functionality is also observed in ICs of P or N-type only transistor processes.

Using NAND and NOR configurations, OR gates can be easily derived.

These are available in both TTL and CMOS logic.

The benefit of using OR type of logic gate is that it finds the maximum number in between the two inputs that are binary in nature.

Here, are the OR gate advantages and disadvantages.

7432 is the TTL type of OR gate which is a quad two-input OR gate that is this IC has four OR gates.

TTL TRANSISTOR DIAGRAM AND GATE SERIES

IN TTL logic, OR gate series is available in 7000. 4072 is the CMOS type OR gate with 4-inputs.4075 is the CMOS OR gate with 3-inputs.IN CMOS logic, the OR gates are available from the 4000 series. This section describes on what are the various configurations of OR gates with the TTL and CMOS logic. OR gate is present in both CMOS and TTL logics where TTL stands for Transistor-Transistor logic and CMOS stands for complementary MOSFET ICs. When the supply voltage is more than the +SVDC voltage, then it may cause damage to IC. The 14 th pin is a Vcc terminal where the maximum supply voltage is given to this pin so that the IC gets activated and the 7 th pin is connected to the ground. Pins 12 and 13 are the inputs for gate 4 and pin 11 is the output for gate 4.Pins 9 and 10 are the inputs for gate 3 and pin 8 is the output for gate 3.Pins 4 and 5 are the inputs for gate 2 and pin 6 is the output for gate 2.Pins 1 and 2 are inputs for gate 1 and pin 3 is the output for gate 1.This theorem states that the product of the complement of inputs is equal to the complement of the sum of the inputs. To implement an OR logic gate using the NAND gate, it is suggested to know about DeMorgan’s theorem. This is the working scenario of the OR type of logic gate using transistors. So that the supply voltage will appear at the output which is logic HIGH or logic 1 This makes that transistor T C does not receive enough potential and it will be in OFF condition. Then, current starts to flow to the ground via this path and the +5V will be dropped down at resistor R. Here, the supply voltage will find a path to the ground terminal through both the transistors T A and T B or either of them. This makes the transistors T A and T B or either of the transistor to be in an ON state. When both the input pins X and Y or either of the inputs is applied with high logic (+5V) which means the base terminals of both the transistors have +5V voltage. Ideally, the transistor T C has some voltage drop (0.6V – 0.7V) across it and this voltage appears at the output which is considered as 0. As the third transistor T C is in ON condition, it performs as short-circuited device and the entire +5V gets dropped down to the ground and output appears to be logic LOW (0V).

Here, +5V voltage moves to the ground through R1 and transistor T C. This makes the transistor T C get the required amount of potential and it will be in an ON state. At this condition, the supply voltage of +5V will not have a path to pass to the ground via any one of the transistors T A and T B. When the input pins X and Y are provided with ‘0’ Volts or when both the pins are grounded, then the transistors T A and T B move into OFF condition correspondingly. Below is the circuit diagram of a two-input OR logic gate using a transistor. The operation and construction of an OR logic gate can also be derived using a transistor. When both the inputs are grounded or provided with 0V, then there will be no voltage at the output and considered as logic LOW. Then the 4.4V voltage appears at the output. When both the inputs are provided with a supply voltage of +5V, both the diodes will move into forward-biased state. This 4.4V or 4.3V is ideally taken into consideration as logic HIGH. In practical scenarios, the entire supply voltage +5V will not be present at the output, some level of voltage drop (0.6V – 0.7V) happens at the diode and the rest of the voltage level (4.3V or 4.4V) passes to an output pin. So, the +5V voltage appears at output Z which means the output is logic HIGH. Whereas when either of the inputs is provided with a supply voltage of +5V, then the corresponding diode moves into forward biased condition and operates as a short, circuited device. As per the above circuit diagram, when the inputs X and Y are provided with 0V, then the output X shows no voltage.

Ttl transistor diagram and gate