APPLICATION INFORMATION

SHUTDOWN FUNCTION

DRIVING A CAPACITIVE LOAD

Input

Output

+

−

Input

Output

+

−

Snubber

C

(a)

(b)

S0048-03

OFFSET VOLTAGE

V

OO +

V

IO

1 )

R

F

R

G

" IIB) RS 1 )

R

F

R

G

" IIB* RF

+

−

+

S0094-01

TLV4110-EP, TLV4111-EP

TLV4112-EP, TLV4113-EP

Two members of the TLV411x family (TLV4110/3) have a shutdown terminal for conserving battery life in

portable applications. When the shutdown terminal is tied low, the supply current is reduced to just nano amps

per channel, the amplifier is disabled, and the outputs are placed in a high-impedance mode. In order to save

power in shutdown mode, an external pullup resistor is required; therefore, to enable the amplifier, the shutdown

terminal must be pulled high. When the shutdown terminal is left floating, care should be taken to ensure that

parasitic leakage current at the shutdown terminal does not inadvertently place the operational amplifier into

shutdown.

When the amplifier is configured in this manner, capacitive loading directly on the output decreases the device's

phase margin, leading to high-frequency ringing or oscillations. Therefore, for capacitive loads of greater than

Figure 27. A maximum value of 20

Ω is recommended for most applications.

Figure 27. Driving a Capacitive Load

the corresponding gains. The following schematic and formula can be used to calculate the output offset voltage.

Figure 28. Output Offset Voltage Model

12

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