Figure 3 shows the output waveform.

If bipolar transistor power dissipation is not tolerable, the

switch could be by a N-channel enhancement mode MOS-

FET.

2.7V SINGLE SUPPLY 2:1 MUX

The schematic show in Figure 4 will function as a 2:1 MUX

operating on a single 2.7V power supply, by utilizing the

shutdown feature of the LMV118.

Figure 5 shows the MUX output when selecting between a

1MHz sine and a 250kHz triangular waveform.

As can be seen in Figure 5, the output is well behaved and

there are no spikes or glitches due to the switching. Switch-

ing times are approximately around 500ns based on the time

when the output is considered “valid”.

20080764

FIGURE 2. Active Pull-Down Schematic

20080736

FIGURE 3. Output Held Low by Active Pull-Down

Circuit

20080758

FIGURE 4. 2:1 MUX Operating off a 2.7V Single Supply

20080735

FIGURE 5. 2:1 MUX Output

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