LT6010 Linear Technology Corporation, LT6010 Datasheet - Page 12

• Manufacturer Part Number: LT6010
• Description: 135?a, 14nv/rthz, Rail-to-rail Output Precision Op Amp With Shutdown
• Manufacturer: Linear Technology Corporation

APPLICATIO S I FOR ATIO
LT6010
Shutdown
The LT6010 can be put into shutdown mode to conserve
power. When the SHDN pin is biased at less than 0.2V
above the negative supply, the part operates normally.
When pulled 2V or more above V
drops to about 12 A, shutting down the op amp.
The output of the LT6010 op amp is not isolated from the
inputs while in shutdown mode. Therefore, this shutdown
feature cannot be used for multiplexing applications.
There is an internal 85k resistor at the SHDN pin. If the
SHDN voltage source is more than 2V above the negative
supply, an external series resistor can be placed between
the source and SHDN pin to reduce SHDN pin current (see
Figure 3). For an example of suggested values see Table 1.
The resistors listed ensure that the voltage at the SHDN pin
is 2V above the negative supply.
Table 1
Capacitive Loads
The LT6010 can drive capacitive loads up to 500pF in unity
gain. The capacitive load driving capability increases as
the amplifier is used in higher gain configurations. A small
series resistance between the output and the load further
increases the amount of capacitance that the amplifier can
drive.
12
V
–
+
SHDN
2
3
4
5
V
V
SHDN
(V)
EE
R
SHDN
U
SHDN
Figure 3
U
5
85k
W
–
, the supply current
R
SHDN
NONE
153k
230k
77k
(k )
6010 F03
V
EE
U
Rail-to-Rail Operation
The LT6010 outputs can swing to within millivolts of either
supply rail, but the inputs cannot. However, for most op
amp configurations, the inputs need to swing less than the
outputs. Figure 4 shows the basic op amp configurations,
lists what happens to the op amp inputs and specifies
whether or not the op amp must have rail-to-rail inputs.
Select a rail-to-rail input op amp only when really neces-
sary, because the input precision specifications are usu-
ally inferior.
V
IN
Figure 4. Some Op Amp Configurations Do Not Require
Rail-to-Rail Inputs to Achieve Rail-to-Rail Outputs
NONINVERTING: A
INPUTS MOVE AS MUCH AS
V
MORE
INPUT MAY NOT HAVE TO BE
RAIL-TO-RAIL
IN
V
, BUT THE OUTPUT MOVES
REF
R
G
+
–
V
REF
V
IN
V
R
F
= 1 + R
INVERTING: A
OP AMP INPUTS DO NOT MOVE,
BUT ARE FIXED AT DC BIAS
POINT V
INPUT DOES NOT HAVE TO BE
RAIL-TO-RAIL
R
G
F
/R
G
REF
+
–
V
= –R
V
IN
R
F
F
/R
NONINVERTING: A
INPUTS MOVE AS MUCH AS THE
OUTPUT
INPUT MUST BE RAIL-TO-RAIL
FOR OVERALL CIRCUIT
RAIL-TO-RAIL PERFORMANCE
G
+
–
V
= 1
sn6010 6010fs
6010 F04