0

5

10

15

20

25

30

35

40

45

50

10p

100p

1n

Capacitive Load (F)

0

25

50

±

+

+ 18 V

± 18 V

OPA192

+

±

G = -1

C013

R

R

R

0

5

10

15

20

25

30

35

40

45

50

10p

100p

1n

Capacitive Load (F)

0

25

50

C013

R

R

R

±

+

+ 18 V

± 18 V

OPA192

+

±

G = +1

OPA192

OPA2192

OPA4192

www.ti.com

SBOS620A – DECEMBER 2013 – REVISED JANUARY 2014

OVERLOAD RECOVERY

Overload recovery is defined as the time it takes for the op amp output to recover from a saturated state to a

linear state. The output devices of the op amp enter a saturation region when the output voltage exceeds the

rated operating voltage, either due to the high input voltage or the high gain. After the device enters the

saturation region, the charge carriers in the output devices require time to return back to the linear state. After

the charge carriers return back to the linear state, the device begins to slew at the specified slew rate. Thus, the

propagation delay in case of an overload condition is the sum of the overload recovery time and the slew time.

The overload recovery time for the OPAx192 is approximately 200 ns.

GENERAL LAYOUT GUIDELINES

For best operational performance of the device, use good printed circuit board (PCB) layout practices, including:

•

Connect low-ESR, 0.1-µF ceramic bypass capacitors between each supply pin and ground, placed as

close to the device as possible. A single bypass capacitor from V+ to ground is applicable to single-

supply applications.

•

In order to reduce parasitic coupling, run the input traces as far away from the supply lines as possible.

•

A ground plane helps distribute heat and reduces EMI noise pickup.

•

Place the external components as close to the device as possible. This configuration prevents parasitic

errors (such as the Seebeck effect) from occurring.

CAPACITIVE LOAD AND STABILITY

The OPA192 features a patented output stage capable of driving large capacitive loads, and in a unity-gain

configuration, can directly drive up to 1 nF of pure capacitive load. Increasing the gain enhances the ability of the

amplifier to drive greater capacitive loads, as shown in Figure 50 and Figure 51. The particular op amp circuit

configuration, layout, gain, and output loading are some of the factors to consider when establishing whether an

amplifier will be stable in operation.

Figure 50. Small-Signal Overshoot vs Capacitive

Figure 51. Small-Signal Overshoot vs Capacitive

Load (100-mV output step)

Load (100-mV output step)

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Product Folder Links: OPA192 OPA2192 OPA4192