ADP194

Rev. 0 | Page 9 of 12

APPLICATIONS INFORMATION

GROUND CURRENT

The major source for ground current in the ADP194 is the 4 MΩ

pull-down resistor on the enable (EN) pin. Figure 16 shows

1.1 V to 3.6 V.

0

1

2

3

4

5

6

7

10

100

1000

Figure 16. Ground Current vs. Load Current, Different Input Voltages

As shown in Figure 17, an increase in ground current can occur

level shift circuitry as it translates an EN signal ≥ 1.1 V to

14

12

10

8

6

4

2

0

3.5

0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 2.7

3.3

3.1

2.9

ENABLE FEATURE

The ADP194 uses the EN pin to enable and disable the VOUT

pin under normal operating conditions. As shown in Figure 18,

when a rising voltage on EN crosses the active threshold, VOUT

turns on. When a falling voltage on EN crosses the inactive

threshold, VOUT turns off.

2.0

1.8

1.6

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0

1.2

0

0.4 0.5 0.6 0.7

0.1 0.2 0.3

0.8 0.9 1.0 1.1

The EN input has built-in hysteresis, as shown in Figure 18.

The hysteresis prevents on/off oscillations that can occur due to

voltage; therefore, these thresholds vary with changing input

voltage. Figure 19 shows typical EN active/inactive thresholds

when the input voltage varies from 1.1 V to 3.6 V.

1.15

1.05

0.95

0.85

0.75

0.65

0.55

0.45

0.35

EN ACTIVE

EN INACTIVE