Datasheet

AD8061/AD8062/AD8063 Data Sheet
Rev. J | Page 18 of 20
MULTIPLEXER
The AD8063 has a disable pin used to power down the ampli-
fier to save power or to create a mux circuit. If two (or more)
AD8063 outputs are connected together, and only one is enabled,
then only the signal of the enabled amplifier will appear at the
output. This configuration is used to select from various input
signal sources. Additionally, the same input signal is applied to
different gain stages, or differently tuned filters, to make a gain-
step amplifier or a selectable frequency amplifier.
Figure 56 shows a schematic of two AD8063 devices used to
create a mux that selects between two inputs. One of these is a
1 V p-p, 3 MHz sine wave; the other is a 2 V p-p, 1 MHz sine wave.
49.9Ω
1kΩ
+4V
1
–4V
49.9Ω
TIME
BASE
OUT
TIME
BASE
IN
1V p-p
3MHz
2V p-p
1MHz
V
OUT
49.9Ω
SELECT
HCO4
1kΩ
10µF
0.1µF
10µF
0.1µF
AD8063
49.9
Ω
1kΩ
+4V
1
–4V
1k
Ω
10µF
0.1µF
10µF
0.1µF
AD8063
01065-056
Figure 56. Two-to-One Multiplexer Using Two AD8063s
The select signal and the output waveforms for this circuit are
shown in Figure 57. For synchronization clarity, two different
frequency synthesizers, whose time bases are locked to each
other, generate the signals.
1V
2V
2µs
SELECT
OUTPUT
01065-057
Figure 57. AD8063 Mux Output