TLV4110, TLV4111, TLV4112, TLV4113

FAMILY OF HIGH OUTPUT DRIVE OPERATIONAL

AMPLIFIERS WITH SHUTDOWN

SLOS289A – DECEMBER 1999 – REVISED APRIL 2000

11

POST OFFICE BOX 655303

APPLICATION INFORMATION

shutdown function

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, thererfore, 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.

driving a capacitive load

When the amplifier is configured in this manner, capacitive loading directly on the output will decrease the

device’s phase margin leading to high frequency ringing or oscillations. Therefore, for capacitive loads of greater

in Figure 24. A maximum value of 20

Ω should work well for most applications.

CLOAD

RF

Input

Output

RG

RNULL

+

–

RL

CL

RF

Input

Output

RG

RNULL

+

–

RL

Snubber

C

(a)

(b)

Figure 24. Driving a Capacitive Load

offset voltage

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

voltage:

V

OO +

V

IO

1

)

R

F

R

G

" I

IB

)

R

S

1

)

R

F

R

G

" I

IB–

R

F

+

–

VI

+

RG

RS

RF

IIB–

VO

IIB+

Figure 25. Output Offset Voltage Model