ADP195 Data Sheet
Rev. C | Page 10 of 12
APPLICATIONS INFORMATION
GROUND CURRENT
The major source for ground current in the ADP195 is an internal
4 MΩ pull-down on the enable pin. Figure 22 shows the typical
ground current when V
EN
= V
IN
and varies from 1.2 V to 3.6 V.
0
2
4
6
8
10
0 50 100 150 200 250 300 350 400 450 500
LOAD (mA)
GROUND CURRENT (µA)
08679-017
V
IN
= 1.2V
V
IN
= 1.6V
V
IN
= 2.0V
V
IN
= 2.4V
V
IN
= 2.8V
V
IN
= 3.2V
V
IN
= 3.4V
V
IN
= 3.6V
Figure 22. Ground Current vs. Load Current
As shown in Figure 23, an increase in quiescent current can occur
when V
EN
≠ V
IN
. This is caused by the CMOS logic nature of the
level shift circuitry as it translates an V
EN
signal ≥ 1.2 V to a
logic high. This increase is a function of the V
IN
− V
EN
delta.
0
2
4
6
8
10
12
14
16
0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6
V
EN
(V)
I
GND
µA)
V
IN
= 1.2V
V
IN
= 1.5V
V
IN
= 1.8V
V
IN
= 2.5V
V
IN
= 3.6V
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Figure 23. Typical Ground Current when V
EN
≠ V
IN
ENABLE FEATURE
The ADP195 uses the EN pin to enable and disable the VOUT
pin under normal operating conditions. As shown in Figure 24,
when a rising voltage on V
EN
crosses the active threshold, V
OUT
turns on. When a falling voltage on V
EN
crosses the inactive
threshold, V
OUT
turns off.
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
1.20 0.4 0.5 0.6 0.70.1 0.2 0.3 0.8 0.9 1.0 1.1
V
EN
(V)
V
OUT
(V)
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Figure 24. Typical EN Operation
As shown in Figure 24, the EN pin has hysteresis built in. This
prevents on/off oscillations that can occur due to noise on the
EN pin as it passes through the threshold points.
The EN pin active/inactive thresholds derive from the V
IN
voltage;
therefore, these thresholds vary with the changing input voltage.
Figure 25 shows the typical EN active/inactive thresholds when
the input voltage varies from 1.2 V to 3.6 V.
1.15
1.05
0.95
0.85
0.75
0.65
0.55
0.45
0.35
3.60
1.20
1.35
1.50
1.65
1.80
1.95
2.10
2.25
2.40
2.55
2.70
2.85
3.00
3.15
3.30
3.45
V
IN
(V)
TYPICAL EN THRESHOLDS (V)
EN ACTIVE
EN INACTIVE
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Figure 25. Typical EN Thresholds vs. Input Voltage (V
IN
)
