ADP1196

Data Sheet

Rev. 0 | Page 10 of 12

APPLICATIONS INFORMATION

CAPACITOR SELECTION

Output Capacitor

The ADP1196 is designed for operation with small, space-

saving ceramic capacitors; however, it functions with most

commonly used capacitors when the effective series resistance

(ESR) value is carefully considered. The ESR of the output

capacitor affects the response to load transients. Use a typical

1 µF capacitor with an ESR of 0.1 Ω or less for good transient

response. Using a larger value of output capacitance improves

the transient response to large changes in load current.

Input Bypass Capacitor

Connecting at least 1 µF of capacitance from VIN to GND reduces

the circuit sensitivity to the PCB layout, especially when high

source impedance or long input traces are encountered. When

greater than 1 µF of output capacitance is required, increase the

input capacitor to match it.

GROUND CURRENT

The major source of ground current in the ADP1196 is the

internal charge pump for the field effect transistor (FET) drive

circuitry. Figure 22 shows the typical ground current when

Figure 22. Ground Current vs. Input Voltage, Different Load Currents

ENABLE FEATURE

The ADP1196 uses the VB_EN pin to enable and disable the

VOUT pin under normal operating conditions. As shown in

crosses the active threshold, VOUT turns on. When a falling

threshold, VOUT turns off.

Figure 23. Typical VB_EN Operation

As shown in Figure 23, the VB_EN pin has hysteresis built into

it. This built-in hysteresis prevents on/off oscillations that can

occur due to noise on the VB_EN pin as it passes through the

threshold points.

voltage; therefore, these thresholds vary with changing input

voltages. Figure 24 shows the typical VB_EN active/inactive

threshold when the input voltage varies from 1.83 V to 5.5 V.

INPUT VOLTAGE (V)

0

1.0

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

0

10

20

30

40

50

60

70

80

90

100

0.5

1.5

0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0

0.2

0.4

0.6

0.8

1.0

1.2

ENABLE VOLTAGE (V)

FALLING

RISING

0

0.2

0.4

0.6

0.8

1.0

1.2

1.8

2.2

2.6

3.0

3.4

3.8

4.2

4.6

5.0

5.4

INPUT VOLTAGE (V)