4
FN9217.4
March 11, 2008
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
EN1, EN2 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
POR1
, POR2 PIN CHARACTERISTICS
POR1
, POR2 Thresholds V
POR+
As a percentage of nominal output voltage 91 94 97 %
V
POR-
87 90 93 %
POR1
Delay t
P1LH
1.0 2.0 3.0 ms
t
P1HL
25 µs
POR2
Delay t
P2LH
C
POR
= 0.01µF 100 200 300 ms
t
P2HL
25 µs
POR1
, POR2 Pin Output Low
Voltage
V
OL
@I
OL
= 1.0mA 0.2 V
POR1
, POR2 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 6.5V with a minimum V
IN
of 2.3V; C
IN
= 1µF; C
O
= 1µF;
C
BYP
= 0.01µF; C
POR
= 0.01µF. (Continued)
PARAMETER SYMBOL TEST CONDITIONS
MIN
(Note 8) TYP
MAX
(Note 8) UNITS
V
POR+
V
POR+
V
POR-
<t
P1HL
t
P2LH
t
P1LH
t
P1HL
t
P2HL
<t
P2HL
VO1
VO2
POR1
POR2
EN2
t
EN
V
POR-
FIGURE 1. TIMING PARAMETER DEFINITION
EN1
ISL9000