Refer to the figure given below. What type of device is shown and what input lev

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Question
Refer to the figure given below. What type of device is shown and what input levels are required to turn the LED off?
Options
A. The device is an open-collector AND gate and requires both inputs to be HIGH in order to turn the LED off.
B. The device is a Schottky AND gate and requires only one low input to turn the LED off.
C. The device is an open-collector AND gate and requires only one low input to turn the LED off.
D. The device is a Schottky open-collector AND gate and requires a low on both inputs to turn the LED off.

Correct Answer

The device is an open-collector AND gate and requires both inputs to be HIGH in order to turn the LED off.

1. What are the major differences between the 5400 and 7400 series of ICs?
Options
A. The 5400 series are military grade and require tighter supply voltages and temperatures.
B. The 5400 series are military grade and allow for a wider range of supply voltages and temperatures.
C. The 7400 series are an improvement over the original 5400s.
D. The 7400 series was originally developed by Texas Instruments. The 5400 series was brought out by National Semiconductors after TI's patents expired, as a second supply source.

4. What type of logic circuit is shown below and what logic function is being performed?
Options
A. It is an NMOS AND gate.
B. It is a CMOS AND gate.
C. It is a CMOS NOR gate.
D. It is a PMOS NAND gate.

6. The bipolar TTL logic family that was developed to increase switching speed by preventing transistor saturation is:
Options
A. emitter-coupled logic (ECL).
B. current-mode logic (CML).
C. transistor-transistor logic (TTL).
D. emitter-coupled logic (ECL) and transistor-transistor logic (TTL).

8. What must be done to interface CMOS to TTL?
Options
A. A dropping resistor must be used on the CMOS 12 V supply to reduce it to 5 V for the TTL.
B. As long as the CMOS supply voltage is 5 V, they can be interfaced; however, the fan-out of the CMOS is limited to two TTL gates.
C. A 5 V Zener diode must be placed across the inputs of the TTL gates in order to protect them from the higher output voltages of the CMOS gates.
D. The two series cannot be interfaced without the use of special interface buffers designed for that purpose, such as the open-collector buffers.

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