The problem of interfacing IC logic families that have different supply voltages

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Question
The problem of interfacing IC logic families that have different supply voltages (V_CC's) can be solved by using a:
Options
A. level-shifter
B. tristate shifter
C. decoupling capacitor
D. pull-down resistor

Correct Answer

level-shifter

3. Each programmable array logic (PAL) gate product is applied to an OR gate and, if combinational logic is desired, the product is ORed and then:
Options
A. the polarity fuse is restored
B. sent to an inverter for output
C. sent immediately to an output pin
D. passed to the AND function for output

4. What is the defining difference between microprocessor/DSP systems and other digital systems?
Options
A. The digital system follows a programmed sequence of instructions that the designer specified.
B. The microprocessor follows a programmed sequence of instructions that the designer specified.
C. The digital system is faster.
D. The microprocessor/DSP is faster.

6. Why is the operating frequency for CMOS devices critical for determining power dissipation?
Options
A. At low frequencies, power dissipation increases.
B. At high frequencies, the gate will only be able to deliver 70.7 % of rated power.
C. At high frequencies, charging and discharging the gate capacitance will draw a heavy current from the power supply and thus increase power dissipation.
D. At high frequencies, the gate will only be able to deliver 70.7 % of rated power and charging and discharging the gate capacitance will draw a heavy current from the power supply and thus increase power dissipation.

8. PMOS and NMOS ________.
Options
A. represent MOSFET devices utilizing either P-channel or N-channel devices exclusively within a given gate
B. are enhancement-type CMOS devices used to produce a series of high-speed logic known as 74HC
C. represent positive and negative MOS-type devices, which can be operated from differential power supplies and are compatible with operational amplifiers
D. None of the above

9. The problem of the V_OH(min) of a TTL IC being too low to drive a CMOS circuit and meet the CMOS requirement of V_IH(min) is usually easily overcome by:
Options
A. adding a fixed voltage-divider bias resistive network at the output of the TTL device
B. avoiding this condition and only using TTL to drive TTL
C. adding an external pull-down resistor to ground
D. adding an external pull-up resistor to V_CC

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