Datasheet

Data Sheet ADP198
Rev. G | Page 13 of 16
ENABLE FEATURE
The ADP198 uses the EN pin to enable and disable the VOUT
pin under normal operating conditions. As shown in Figure 25,
when a rising V
EN
voltage crosses the active threshold, VOUT
turns on. When a falling V
EN
voltage crosses the inactive
threshold, VOUT turns off.
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.45
0.50
0.55
0.60
0.65
0.70
0.75
0.80
V
OUT
(V)
ENABLE VOLTAGE (V)
V
IN
RISING
V
IN
FALLING
09484-025
Figure 25. Typical EN Operation
As shown in Figure 25, 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 26 shows the typical EN active/inactive thresholds when
the input voltage varies from 1.65 V to 6.5 V.
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1
2 3
4
5 6 7
ENABLE THRESHOLD (V)
INPUT VO
LTAGE (V)
EN RISE
EN FALL
09484-026
Figure 26. Typical EN Thresholds vs. Input Voltage (V
IN
)