4
FN9231.2
March 28, 2008
DEVICE START-UP CHARACTERISTICS
Device Enable Time t
EN
Time from assertion of the ENx pin to when the output
voltage reaches 95% of the VO (nom)
250 500 µs
LDO Soft-start Ramp Rate t
SSR
Slope of linear portion of LDO output voltage ramp during
start-up
30 60 µs/V
EN PIN CHARACTERISTICS
Input Low Voltage V
IL
-0.3 0.5 V
Input High Voltage V
IH
1.4 V
IN
+0.3 V
Input Leakage Current I
IL
, I
IH
0.1 µA
Pin Capacitance C
PIN
Informative 5 pF
POR
PIN CHARACTERISTICS
POR Thresholds V
POR+
As a percentage of nominal output voltage 91 94 97 %
V
POR-
87 90 93 %
POR
Delay t
PLH
C
POR
= 0.01µF 100 200 300 ms
t
PHL
25 µs
POR Pin Output Low Voltage V
OL
@ I
OL
= 1.0mA 0.2 V
POR
Pin Internal Pull-up
Resistance
R
POR
78 100 180 kΩ
NOTES:
6. Limits established by characterization and are not production tested.
7. VOx = 0.98*VOx(NOM); Valid for VOx greater than 1.85V.
8. Parts are 100% tested at +25°C. Temperature limits established by characterization and are not production tested.
Electrical Specifications Unless otherwise noted, all parameters are guaranteed over the operational supply voltage and temperature
range of the device as follows: T
A
= -40°C to +85°C; V
IN
= (V
O
+ 0.5V) to 5.5V with a minimum V
IN
of 2.3V;
C
IN
=1µF; C
O
= 1µF. (Continued)
PARAMETER SYMBOL TEST CONDITIONS
MIN
(Note 8) TYP
MAX
(Note 8) UNITS
V
POR+
V
POR+
V
POR-
<t
PHL
t
PLH
t
PHL
VO
POR
EN
t
EN
V
POR-
FIGURE 1. TIMING PARAMETER DEFINITION
ISL9001