Datasheet

LTC2953
4
2953f
ELECTRICAL CHARACTERISTICS
The ● denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 2.7V to 27V, unless otherwise noted (Note 2).
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: All currents into pins are positive; all voltages are referenced to
GND unless otherwise noted.
Note 3: The Enable Lock Out time is designed to allow an application to
properly power down such that the next power up sequence starts from a
consistent powered down confi guration.
⎯
P
⎯
B is ignored during this lock out
time. This time delay does not include t
DB, ON
.
Note 4: To manually force a release of the EN/
⎯
E
⎯
N pin, either
⎯
P
⎯
B or UVLO
must be held low for at least t
PD, Min
(internal default power down timer) +
t
PDT
(adjustable by placing external capacitor at PDT pin).
Note 5: The
⎯
K
⎯
I
⎯
L
⎯
L turn on blanking timer period (t
KILL, ON BLANK
) is the
waiting period immediately after enable output is asserted. This blanking
time allows suffi cient time for the DC/DC converter and the μP to perform
power up tasks. The
⎯
K
⎯
I
⎯
L
⎯
L,
⎯
P
⎯
B and UVLO inputs are ignored during this
period. If
⎯
K
⎯
I
⎯
L
⎯
L remains low at the end of this blanking period, the enable
output is released, thus turning off system power.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
PFI(LKG)
⎯
P
⎯
F
⎯
I Leakage Current V
PFI
= 0.5V
V
PFI
= 27V
●
2 ±10
±1
nA
μA
I
PFO(LKG)
⎯
P
⎯
FO Leakage Current V
PFO
= 1V
V
PFO
= 40V
●
2 ±10
±1
nA
μA
I
UVLO(LKG)
UVLO Leakage Current V
UVLO
= 0.5V
V
UVLO
= 27V
●
2 ±10
±1
nA
μA
I
VM(LKG)
VM Input Leakage Current VM = 0.5V
●
2 ±10 nA
I
RST(LKG)
⎯
R
⎯
S
⎯
T Output Leakage Current V
RST
= 3V
●
±0.1 μA
t
PFI
⎯
P
⎯
F
⎯
I Delay to
⎯
P
⎯
F
⎯
O
●
40 100 200 μs
t
RST
Reset Timeout Period
●
140 200 260 ms
t
uv
VM Under Voltage Detect to
⎯
R
⎯
S
⎯
T VM Less Than VM
(TH)
By More Than 1% 250 μs