Current Shareware 1994 January

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Text File | 1993-03-09 | 21KB | 489 lines

245F-1C1 A 6-2 Arrow always points to the "N" material|Metal Oxide Semiconductor forms a capacitor|Which drawings look like a capacitor What is the schematic symbol for an N-channel MOSFET? | ├────── D ├────── D A. │ │ B. │ │ ├─<─┐ G ────>─┤ │ │ │ │ G ─────┘ ├───┴── S ├────── S ├────── D ├────── D C. │ D. │ │ G ────<─┤ │ ├─>─┐ │ │ │ │ ├────── S G ────┘ ├───┴── S * 246F-1C2 B 6-2 Arrow always points to the "N" material|If the channel is "P" type, arrow points out|Which drawings look like a capacitor What is the schematic symbol for an P-channel MOSFET? | E \ ├────── B2 ├────── D A. > │ B. │ │ \│ │ ├─>─┐ ├────── B1 │ │ │ G ─────┘ ├───┴── S ├────── D C. │ │ D. E \ ├────── B2 │ ├─<─┐ < │ │ │ │ \│ G ─────┘ ├───┴── D ├────── B1 * 247F-1C3 C 6-2 Arrow always points to the "N" material|Metal Oxide Semiconductor forms a capacitor|Which drawings look like dual capacitors What is the schematic symbol for an N-channel dual-gate MOSFET? | ├────── D A. /──── C B. │ │ │ / G2 ─────┘ ├─>─┐ B ────┤\ │ │ │ │ < G1 ─────┘ ├───┴── S \──── E ├────── D /──── C C. │ │ D. │ / G2 ─────┘ ├─<─┐ B ────┤\ │ │ │ │ > G1 ─────┘ ├───┴── S \──── E * 248F-1C4 D 6-2 Arrow always points to the "N" material|If the channel is "P" type, arrow points out|Which drawings look like dual capacitors What is the schematic symbol for an P-channel dual-gate MOSFET? | ├────── D ├────── D A. │ │ B. │ │ G2 ─────┘ ├─<─┐ │ ├─>─┐ │ │ │ │ │ │ G1 ─────┘ ├───┴── S G ─────┘ ├───┴── S ├────── D ├────── D C. │ │ D. │ │ │ ├─<─┐ G2 ─────┘ ├─>─┐ │ │ │ │ │ │ G ─────┘ ├───┴── S G1 ─────┘ ├───┴── S * 249F-1C5 D 6-3 Metal Oxide Semiconductor forms a capacitor|This capacitor is very thin, thus it has a |low breakdown(puncture) voltage Why do many MOSFET devices have built-in gate-protective Zener diodes? A. The gate-protective Zener diode provides a voltage reference to provide the correct amount of reverse-bias gate voltage B. The gate-protective Zener diode protects the substrate from excessive voltages C. The gate-protective Zener diode keeps the gate voltage within specifications to prevent the device from overheating D. The gate-protective Zener diode prevents the gate insulation from being punctured by small static charges or excessive voltages * 250F-1D1 C 6-3 Metal Oxide Semiconductor forms a capacitor What do the initials CMOS stand for? A. Common mode oscillating system B. Complementary mica-oxide silicon C. Complementary metal-oxide semiconductor D. Complementary metal-oxide substrate * 251F-1D2 A 6-3 Metal Oxide Semiconductor forms a very thin |capacitor that has a low breakdown(puncture)|voltage, easily damaged by static charges Why are special precautions necessary in handling FET and CMOS devices? A. The are susceptible to damage from static charges B. They have fragile leads that may break off C. They have micro-welded semiconductor junctions that are susceptible to breakage D. They are light sensitive * 252F-1E1 A 6-2 Arrow always points to the "N" material |All FETs have Gates, Drains, and Sources What is the schematic symbol for an N-channel junction FET? | ├────── D E \ ├────── B2 A. │ B. < │ G ────>─┤ \│ │ ├────── B1 ├────── S E \ ├───── B2 ├────── D C. > │ D. │ \│ G ────<─┤ ├───── B1 │ ├────── S * 253F-1E2 D 6-1 A tube is a field effect device, any help?|Usually there is no gate current in a FET |Bipolars have a base current Ib=Ic/ß How does the input impedance of a field-effect transistor compare with that of a bipolar transistor? A. One cannot compare input impedance with out first knowing the supply voltage B. An FET has low input impedance; a bipolar transistor has a high input impedance C. The input impedance of FETs and bipolar transistors is the same D. An FET has high input impedance; a bipolar transistor has a low input impedance * 254F-1E3 D 6-1 All FETs have Gates, Drains, and Sources What are the three terminals of a field-effect transistor? A. Gate 1, gate 2, drain B. Emitter, base, collector C. Emitter, base 1, base 2 D. Gate, drain, source * 255F-1F1 B 6-2 All FETs have Gates, Drains, and Sources|Arrow always points to the "N" material |If the channel is "P" type, arrow points out What is the schematic symbol for an P-channel junction FET? | /──── C ├────── D A. │ / B. │ B ────┤\ G ────<─┤ │ < │ \──── E ├────── S ├────── D /─── C C. │ D. │ / G ────>─┤ B ────┤\ │ │ > ├────── S \─── E * 256F-1F2 A 6-1 Time to go to the A & P|Or was that the N & P? What are the basic types of junction field-effect transistors? A. N-channel and P-channel B. High power and low power C. MOSFET and GaAsFET D. Silicon FET and germanium FET * 257F-2.1 A 6-4 Key words, differential amplifier What is an operational amplifier? A. A high-gain, direct coupled differential amplifier whose characteristics are determined by components external to the amplifier unit B. A high-gain, direct coupled audio amplifier whose characteristics are determined by components external to the amplifier unit C. An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit D. A program subroutine that calculates the gain of an RF amplifier * 258F-2.2 A 6-5 Differential amplifier, two inputs|Looks like a piece of pie What is the schematic symbol for an operational amplifier? | / \ ┌─────── \ A. ───┤ \ B. ───┤ \ │ \ │ ├─── │ ├───── ───┤ / │ / └─────── / ───┤ / \ / ┌───────\ │ \ \ \ │ \ C. ───┤ \ D. │ \ │ ├─── ────┤ ├──── ───┤ / │ / / / │ / └───────/ │ / * 259F-2.3 B 6-4 To B or not to B, that is the...|High input Z will not load previous stage|Low output Z will drive almost anything What would be the characteristics of the ideal op-amp? A. Zero input impedance, infinite output impedance, infinite gain, flat frequency response B. Infinite input impedance, zero output impedance, infinite gain, flat frequency response C. Zero input impedance, zero output impedance, infinite gain, flat frequency response D. Infinite input impedance, infinite output impedance, infinite gain, flat frequency response * 260F-2.4 A 6-5 External components What determines the gain of a closed-loop op-amp circuit? A. The external feedback network B. The collector-to-base capacitance of the PNP stage C. The power supply voltage D. The PNP collector load * 261F-2.5 C 6-6 Differential amplifier, two inputs|Op-amp in a closed-loop condition What is meant by the term op-amp offset voltage? A. The output voltage of the op-amp minus its input voltage B. The difference between the output voltage of the op-amp and the input voltage required in the following stage C. The potential between the amplifier-input terminals of the op-amp in a closed-loop condition D. The potential between the amplifier-input terminals of the op-amp in a open-loop condition * 262F-2.6 D 6-4 High input Z will not load previous stage|Low output Z will drive almost anything What is the input impedance of a theoretically ideal op-amp? A. 100 ohms B. 1000 ohms C. Very low D. Very high * 263F-2.7 A 6-4 High input Z will not load previous stage|Low output Z will drive almost anything What is the output impedance of a theoretically ideal op-amp? A. Very low B. Very high C. 100 ohms D. 1000 ohms * 264F-3.1 D 6-7 Phase detector |Low-pass filter|VCO What is a phase-locked loop circuit? A. An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator B. An electronic circuit also known as a monostable multivibrator C. An electronic circuit consisting of a precision push-pull amplifier with a differential input D. An electronic servo loop consisting of a phase detector, a low-pass filter, and voltage-controlled oscillator * 265F-3.2 D 6-7 Frequency synthesis is one use What functions are performed by a phase-locked loop? A. Wideband AF and RF power amplification B. Comparison of two digital input signals, digital pulse counter C. Photovoltaic conversion, optical coupling D. Frequency synthesis, FM demodulation * 266F-3.3 B 6-7 Phase-locked loop A circuit compares the output from a voltage-controlled oscillator and a frequency standard. The difference between the two frequencies produces an error voltage that changes the voltage- controlled oscillator frequency. What is the name of the circuit? A. A doubly balanced mixer B. A phase-locked loop C. A differential voltage amplifier D. A variable frequency oscillator * 267F-4.1 B 6-9 Tamale & Taco for Lunch What do the initials TTL stand for? A. Resistor-transistor logic B. Transistor-transistor logic C. Diode-transistor logic D. Emitter-coupled logic * 268F-4.2 C 6-9 Five Alive What is the recommended power supply voltage for TTL series integrated circuits? A. 12.00 volts B. 50.00 volts C. 5.00 volts D. 13.60 volts * 269F-4.3 A 6-10 TTL inputs must be pulled low |since they assume a high logic|state if they are left open What logic state do the inputs of a TTL device assume if they are left open? A. A high logic state B. A low logic state C. The device becomes randomized and will not provide consistent high or low logic states D. Open inputs on a TTL device are ignored * 270F-4.4 A 6-9 2.0 to 5.5 What level of input voltage is high in a TTL device operating with a 5-volt power supply? A. 2.0 to 5.5 volts B. 1.5 to 3.0 volts C. 1.0 to 1.5 volts D. -5.0 to -2.0 volts * 271F-4.5 C 6-9 -0.6 to 0.8 What level of input voltage is low in a TTL device operating with a 5-volt power supply? A. -2.0 to -5.5 volts B. 2.0 to 5.5 volts C. -0.6 to 0.8 volts D. -0.8 to 0.4 volts * 272F-4.6 D 6-10 To bypass switching transients and prevent|them from appearing on the supply line Why do circuits containing TTL devices have several bypass capacitors per printed circuit board? A. To prevent RFI to receivers B. To keep the switching noise within the circuit, thus eliminating RFI C. To filter out switching harmonics D. To prevent switch transients from appearing on the supply line * 273F-5.1 B 6-10 Complementary Metal Oxide Semiconductor |Are Ns & Ps anything like males & females? What is a CMOS IC? A. A chip with only P-channel transistors B. A chip with P-channel and N-channel transistors C. A chip with only N-channel transistors D. A chip with only bipolar transistors * 274F-5.2 B 6-10 Define devices, digital logic ICs?|In that case, I'll take B What is one major advantage of CMOS over other devices? A. Small size B. Low current consumption C. Low cost D. Ease of circuit design * 275F-5.3 C 6-10 CMOS digital ICs output switches almost the|entire power supply voltage and the input |switching point is half of the PS voltage Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply? A. Larger bypass capacitors are used in CMOS circuit design B. The input switching threshold is about two times the power supply voltage C. The input switching threshold is about one-half the power supply voltage D. Input signals are stronger * 276F-6.1 C 6-11 Look mom, |I,m on the|Vidicon What is the name for a vacuum tube that is commonly found in television cameras used for amateur television? A. A traveling-wave tube B. A klystron tube C. A vidicon tube D. A cathode-ray tube * 277F-6.2 D 6-11 Key word Field, Electromagnetic this time How is the electron beam deflected in a vidicon? A. By varying the beam voltage B. By varying the bias voltage on the beam forming grids in the tube C. By varying the beam current D. By varying electromagnetic fields * 278F-6.3 D 6-12 And I thought static meant|that it didn't move or change What type of CRT deflection is better when high-frequency waves are to be displayed on the screen? A. Electromagnetic B. Tubular C. Radar D. Electrostatic * 279G-1A1 D 7-1 One for the Flip|One for the Flop What is a flip-flop circuit? A. A binary sequential logic element with one stable state B. A binary sequential logic element with eight stable states C. A binary sequential logic element with four stable states D. A binary sequential logic element with two stable states * 280G-1A2 A 7-1 The output is either a 1 or a 0. Therefore|it can only hold a single bit of information How many bits of information can be stored in a single flip-flop circuit? A. 1 B. 2 C. 3 D. 4 * 281G-1A3 C 7-1 A flip-flop aka a bistable|multivibrator is sometimes|called a latch What is a bistable multivibrator circuit? A. An "AND" gate B. An "OR" gate C. A flip-flop D. A clock * 282G-1A4 C 7-4 The first trigger changes the ouput.|The second pulse changes it back. So|you get one level change per trigger How many output changes are obtained for every two trigger pulses applied to the input of a bistable T flip-flop circuit? A. No output level changes B. One output level change C. Two output level changes D. Four output level changes * 283G-1A5 C 7-4 A bistable multivibrator, aka a flip-flop,|divides by two. The first trigger changes|the ouput. The second pulse changes it back The frequency of an ac signal can be divided electronically by what type of digital circuit? A. A free-running multivibrator B. An OR gate C. A bistable multivibrator D. A astable multivibrator * 284G-1A6 C 7-1 A flip-flop aka a bistable|multivibrator is sometimes|called a latch What type of digital IC is also known as a latch? A. A decade counter B. An OR gate C. A flip-flop D. An op-amp * 285G-1A7 B 7-4 A flip-flop divides by two. The first|trigger changes the ouput. The second|pulse changes it back How many flip-flops are required to divide a signal frequency by 4? A. 1 B. 2 C. 4 D. 8 * 286G-1B1 D 7-6 Define Astable? |An Unstable barn? What is an astable multivibrator? A. A circuit that alternates between two stable states B. A circuit that alternates between a stable state and an unstable state C. A circuit set to block either a 0 pulse or a 1 pulse and pass the other D. A circuit that alternates between two unstable states * 287G-1B2 A 7-4 A circuit that can be switched momentarily|to the opposite binary state What is an monostable multivibrator? A. A circuit that can be switched momentarily to the opposite binary state and then returns after a set time to its original state B. A "clock" circuit circuit that produces a continuous square wave oscillating between 1 and 0 C. A circuit designed to store one bit of data in either the 0 or the 1 configuration D. A circuit that maintains a constant output voltage, regardless of variations in the input voltage * 288G-1C1 A 7-7 1 AND 1 = 1|0 AND 1 = 0|1 AND 0 = 0 What is an AND gate? A. A circuit that produces a logic "1" at its output only if all inputs are logic "1" B. A circuit that produces a logic "0" at its output only if all inputs are logic "1" C. A circuit that produces a logic "1" at its output if only one input is a logic "1" D. A circuit that produces a logic "1" at its output if all inputs are logic "0" * 289G-1C2 A 7-7 Two (or more) inputs, one output|Left side drawn with straight line What is the schematic symbol for an AND gate? | ┌─────── \ │ \ A. ───┤ \ B. │ \ │ ├─── │ \ ───┤ / ────┤ ├──── └─────── / │ / │ / │ / ┌───────\ \ \ C. ───┤ \ D. │ \ │ ├─── │ \ ───┤ / ────┤ ├O─── / / │ / └───────/ │ / * 290G-1C3 D 7-8 Not(1 AND 1) = 0 What is a NAND gate? A. A circuit that produces a logic "0" at its output only when all inputs are logic "0" B. A circuit that produces a logic "1" at its output only when all inputs are logic "1" C. A circuit that produces a logic "0" at its output if some but not all of its inputs are logic "1" D. A circuit that produces a logic "0" at its output only when all inputs are logic "1" * 291G-1C4 B 7-8 NOT bubble on output of AND gate|Left side drawn with straight line What is the schematic symbol for an NAND gate? | ┌───────\ \ \ ┌─────── \ A. ──O┤ \ B. ───┤ \ │ ├O── │ ├O── ──O┤ / ───┤ / / / └─────── / └───────/ ┌───────\ \ \ ┌─────── \ C. ───┤ \ D. ──O┤ \ │ ├O── │ ├O── ───┤ / ──O┤ / / / └─────── / └───────/ * 292G-1C5 A 7-8 1 OR 1 = 1|1 OR 0 = 1|0 OR 1 = 1 What is an OR gate? A. A circuit that produces a logic "1" at its output if any input is logic "1" B. A circuit that produces a logic "0" at its output if any input is logic "1" C. A circuit that produces a logic "0" at its output if all inputs are logic "1" D. A circuit that produces a logic "1" at its output if all inputs are logic "0" * 293G-1C6 D 7-8 Two (or more) inputs, one output|Left side drawn with curved line What is the schematic symbol for an OR gate? | ┌─────── \ │ \ A. ───┤ \ B. │ \ │ ├─── ────┤ ├O─── ───┤ / │ / └─────── / │ / │ \ ┌───────\ │ \ \ \ C. │ \ D. ───┤ \ ────┤ ├──── │ ├─── │ / ───┤ / │ / / / │ / └───────/ *