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How are diodes used as logic gates?
Diode logic gates use diodes to perform OR and AND logic functions as shown in the circuit diagram. Connection of the LED at the output is optional which simply displays the logical state of the output, i.e. the logic state of output is 0 or 1, if LED is off or on, respectively.
What are disadvantages of using diodes as Gates?
Diode logic (DL) uses diodes to implement logical functions like AND and OR. But the disadvantage is that it can not perform NOT operation. As AND and OR are not complete functions by themselves, they can not perform several logic functions without NOT.
How many diodes is needed to construct an AND gate?
Diode Logic AND gate (wired AND connection) When both inputs are at logic “1″, the two diodes are reverse biased and there is no current flowing to ground. Therefore the output is logic “1” because there is no voltage drop across the resistor R.
When to use an ideal diode MOSFET circuit?
If the battery voltage is less than 10V then a logic-level type MOSFET should be used which have gate-source threshold voltages (Vgsth) of less than 2V. One of these circuits can be used at the output of each battery; however, many are in parallel.
When to use a MOSFET gate drive circuit?
When the power-supply IC and MOS transistor are selected, it is especially important to select an appropriate driver circuit to connect the IC to the transistor. A good MOSFET driver circuit has the following requirements: 1.
Why does the p-MOSFET gate turn on in the forward direction?
In the forward direction (output voltage lower than the battery voltage) the current mirror becomes unbalanced due to the difference in emitter voltages, such as to turn Q2 off, which puts the P-MOSFET gate near ground potential, turning it on. This allows current to flow from the battery to the output (left to right) with a low drop.
How is the voltage drop across the MOSFET maintained?
The voltage drop across the N-channel MOSFET source-to-drain is regulated to a small reference voltage by an amplifier. In Figure 4a, a 15mV difference between the input supply voltage (NFET source) and the load voltage (NFET drain) is maintained by controlling the gate voltage (hence the MOSFET resistance) even as the load current changes.