LT6010

12

6010f

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.

drops to about 12

µA, 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

2

NONE

3

77k

4

153k

5

230k

APPLICATIO S I FOR ATIO

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.

6010 F03

SHDN

85k

5

+

–

Figure 3

INPUTS MOVE AS MUCH AS

MORE

INPUT MAY NOT HAVE TO BE

RAIL-TO-RAIL

INPUTS MOVE AS MUCH AS THE

OUTPUT

INPUT MUST BE RAIL-TO-RAIL

FOR OVERALL CIRCUIT

RAIL-TO-RAIL PERFORMANCE

OP AMP INPUTS DO NOT MOVE,

BUT ARE FIXED AT DC BIAS

INPUT DOES NOT HAVE TO BE

RAIL-TO-RAIL

–

+

–

+

6010 F04

–

+

Figure 4. Some Op Amp Configurations Do Not Require

Rail-to-Rail Inputs to Achieve Rail-to-Rail Outputs

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.