Data Sheet ADG3233
Rev. C | Page 13 of 16
THEORY OF OPERATION
The ADG3233 is a bypass switch designed on a submicron
process that operates from supplies as low as 1.65 V. The device
is guaranteed for operation over the supply range 1.65 V to 3.6 V. It
operates from two supply voltages, allowing bidirectional level
translation, that is, it translates low voltages to higher voltages
and vice versa. The signal path is unidirectional, meaning data
may only flow from A → Y.
A1 AND EN INPUT
The A1 and enable (
EN
) inputs have V
IL
/V
IH
logic levels so that
the part can accept logic levels of V
OL
/V
OH
from Device 0 or the
controlling device independent of the value of the supply being
used by the controlling device. These inputs (A1,
EN
) are
capable of accepting inputs outside the V
CC1
supply range. For
example, the V
CC1
supply applied to the bypass switch could be
1.8 V while Device 0 could be operating from a 2.5 V or 3.3 V
supply rail, there are no internal diodes to the supply rails, so
the device can handle inputs above the supply but inside the
absolute maximum ratings.
NORMAL OPERATION
Figure 35 shows the bypass switch being used in normal mode.
In this mode, the signal paths are from A1 → Y1 and A2 → Y2.
The device will level translate the signal applied to A1 to a V
CC1
logic level (this level translation can be either to a higher or
lower supply) and route the signal to the Y1 output, which
will have standard V
OL
/V
OH
levels for V
CC1
supplies. The signal
is then passed through Device 1 and back to the A2 input pin
of the bypass switch.
The logic level inputs of A2 are with respect to the V
CC1
supply.
The signal will be level translated from V
CC1
to V
CC2
and routed
to the Y2 output pin of the bypass switch. Y2 output logic levels
are with respect to the V
CC2
supply.
CC2
CC1
CC0
SIGNAL INPUT
A1
A2
Y1
Y2
LOGIC 1
SIGNAL OUTPUT
DEVICE 0 DEVICE 1 DEVICE 2
V
CC2
V
CC1
03297-035
EN
BYPASS SWITCH
Figure 35. Bypass Switch in Normal Mode
