Transcript Ch13thru14

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Microelectronic Circuits 4/e
©1999 Oxford University Press.
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Fig. 13.2 Typical voltage transfer characteristic (VTC) of a logic inverter, illustrating the definition of the critical points.
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Fig. 13.3 Definitions of propagation delays and switching times of the logic inverter.
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Fig. 13.4 (a) The CMOS inverter and (b) its representation as a pair of switches operated in a complementary fashion.
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Fig. 13.5 The voltage transfer characteristic (VTC) of the CMOS inverter when QN and QP are matched.
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Fig. 13.12 A two-input CMOS NOR gate.
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Fig. 13.13 A two-input CMOS NAND gate.
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Fig. 13.16 Proper transistor sizing for a four-input NOR gate. Note that n and p denote the (W/L) rations of QN and QP, respectively, of
the basic inverter.
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Fig. 13.17 Proper transistor sizing for a four-input NAND gate. Note that n and p denote the (W/L) rations of QN and QP, respectively,
of the basic inverter.
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Fig. 13.21 VTC for the pseudo-NMOS inverter. This curve is plotted for VDD = 5, Vtn = -Vtp = 1 V, and r = 9.
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Fig. 13.33 (a) basic structure of dynamic-MOS logic circuits; (b) waveform of the clock needed to operate the dynamic-logic circuit;
and (c) an example circuit.
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Fig. 13.34 (a) Charge sharing. (b) Adding a permanently turned-on transistor QL solves the charge-sharing problem at the expense of
static-power dissipation.
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Fig. 13.35 Two single-input dynamic-logic gates connected in cascade. With the input A high, during the evaluation phase CL2 will
partially discharge and the output at Y2 will fall lower than VDD, which can cause logic malfunction.
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Fig. 13.37 (a) Two single-input DOMINO CMOS logic gates connected in cascade. (b) Waveforms during the evaluation phase.
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Fig. 13.38 (a) Basic latch. (b) The latch with the feedback loop opened. (c) Determining the operating point of the latch.
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Fig. 13.40 CMOS implementation of a clocked SR flip-flop. The clock signal is denoted by .
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Fig. 13.42 A simpler CMOS implementation of the clocked SR flip-flop. This circuit is popular as the basic cell in the design of static
random-access memory chips.
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Fig. 13.44 A simple implementation of the D flip-flop. The circuit in (a) utilizes the two-phase nonoverlapping clock whose
waveforms are shown in (b).
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Fig. 13.45 (a) A master-slave D flip-flop. Note that the switches can be, and usually are, implemented with CMOS transmission gates.
(b) Waveforms of the two-phase nonoverlapping clock required.
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Fig. 13.47 Monostable circuit using CMOS NOR gates. Signal source vI supplies the trigger pulses.
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Fig. 13.50 Timing diagram for the monostable circuit in Fig. 13.47.
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Fig. 13.52 (a) A simple astable multivibrator circuit using CMOS gates. (b) Waveforms for the astable circuit in (a). The diodes at
the gate input are assumed ideal and thus limit the voltage vI1 to 0 and VDD.
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Fig. 13.53 (a) A ring oscillator formed by connecting three inverters in cascade. (Normally at least five inverters are used.) (b) The
resulting waveform. Observe that the circuit oscillates with frequency 1/(6tp).
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Fig. 13.54 A 2M+N-bit memory chip organized as an array of 2M rows x 2N columns.
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Fig. 13.55 A CMOS SRAM memory cell.
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Fig. 13.60 A differential sense amplifier connected to the bit lines of a particular column. This arrangement can be used directly for
SRAMs (which can utilize both B and B lines). DRAMs can be turned into differential circuits by using the “dummy cell” arrangement
shown in Fig. 13.61.
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Fig. 13.61 Waveforms of vB before and after activating the sense amplifier. In a read-1 operation, the sense amplifier causes the initial
small increment V(1) to grow exponentially to VDD. In a read-0 operation, the negative V(0) grows to 0. Complementary signal
waveforms develop on the B line.
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Fig. 13.62 Arrangement for obtaining differential operation from the single-ended DRAM cell. Note the dummy cells at the far right
and far left.
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Fig. 13.63 A NOR address decoder in array form. One out of eight lines (row lines) is selected using a 3-bit address.
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Fig. 13.64 A column decoder realized by a combination of a NOR decoder and a pass-transistor multiplexer.
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Fig. 13.65 A free column decoder. Note that the colored path shows the transistors that are conducting when A0 = 1, A1 = 0, and A2 =
1, the address that results in connecting B5 to the data line.
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Fig. 13.66 A simple MOS ROM organized as 8 words x 4 bits.
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Fig. 13.67 (a) Cross section and (b) circuit symbol of the floating-gate transistor used as an EPROM cell.
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Fig. 13.68 Illustrating the shift in the iD-vGS characteristic of a floating-gate transistor as a result of programming.
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Fig. 13.69 The floating-gate transistor during programming.
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Fig. 14.1 Switching times of the BJT in the simple inverter circuit of (a) when the input v1 has the pulse waveform on (b). The effects
of stored base charge following the return of v1 to V1 are explained in conjunction with Eqs. (14.2) and (14.3).
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Fig. 14.20 Analysis of the TTL gate with the input high. The circled numbers indicate the order of the analysis steps.
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Fig. 14.22 Analysis of the TTL gate when the input is low. The circled numbers indicate the order of the analysis steps.
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Fig. 14.23 The TTL gate and its voltage transfer characteristic.
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Fig. 14.24 The TTL NAND gate.
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Fig. 14.25 Structure of the multiemitter transistor Q1.
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Fig. 14.28 A Schottky TTL (known as STTL) NAND gate.
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Fig. 14.33 Basic gate circuit of the ECL 10K family.
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Fig. 14.35 Simplified version of the ECL gate for the purpose of finding transfer characteristics.
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Fig. 14.36 The OR transfer characteristic vOR versus v1, for the circuit in Fig. 14.35.
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Fig. 14.38 The NOR transfer characteristic, vNOR versus v1, for the circuit in Fig. 14.35.
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Fig. 14.44 Development of the BiCMOS inverter circuit: (a) The basic concept is to use an additional bipolar transistor to increase the
output current drive of each QN and QP of the CMOS inverter; (b) the circuit in (a) can be thought of as utilizing these composite devices;
(c) to reduce the turn-off times of Q1 and Q2, “bleeder resistors” R1 and R2 are added; (d) implementation of the circuit in (e) using
NMOS transistors to realize the resistors; (e) an improved version of the circuit in (c) obtained the lower end of R1 to the output mode.
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