Datasheet

AD8331/AD8332/AD8334
Rev. G | Page 29 of 56
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–3 –2 –1 0 1 2 3
V
OH
,
V
OL
(V)
V
INH
(V)
03199-080
R
CLMP
= 
R
CLMP
= 
8.8k
8.8k
3.5k
3.5k
R
CLMP
= 1.86k
Output Clamping
Outputs are internally limited to a level of 4.5 V p-p differential
when operating at a 2.5 V common-mode voltage. The postamp
implements an optional output clamp engaged through a resistor
from R
CLMP
to ground. Table 8 shows a list of recommended
resistor values.
Output clamping can be used for ADC input overload protection, if
needed, or postamp overload protection when operating from a
lower common-mode level, such as 1.5 V. The user should be
aware that distortion products increase as output levels approach
the clamping levels, and the user should adjust the clamp resistor
accordingly. For additional information, see the Applications
Information section.
The accuracy of the clamping levels is approximately ±5% in LO
or HI mode. Figure 80 illustrates the output characteristics for a
few values of R
CLMP
.
Figure 80. Output Clamping Characteristics