LT3420/LT3420-1
The
q
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= V
BAT
= 3.3V, V
CHARGE
= V
CC
unless otherwise noted. (Note 3)
PARAMETER
Switch V
CESAT
Switch Leakage Current
CHARGE Input Voltage High
CHARGE Input Voltage Low
CHARGE Pin Bias Current
DONE Output Signal High
DONE Output Signal Low
V
CHARGE
= 3V
V
CHARGE
= 0V
100k from V
CC
to DONE
33µA into DONE Pin
4.5
0.01
3.3
100
200
CONDITIONS
LT3420, SW = 1A
LT3420-1, SW = 0.5A
V
SW
= 38V (LT3420), V
SW
= 50V (LT3420-1)
1.5
0.2
15
0.1
MIN
TYP
220
130
0.01
MAX
340
230
1
UNITS
mV
mV
µA
V
V
µA
µA
V
mV
ELECTRICAL CHARACTERISTICS
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
Rated breakdown with LT3420 in power delivery mode and power
switch off.
Note 3:
The LT3420/LT3420-1 are guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the –40°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 4:
Bias current flows out of R
FB
pin.
Note 5:
Current limit guaranteed by design and/or correlation to static test.
TYPICAL PERFOR A CE CHARACTERISTICS
Graphs apply to both the LT3420 and LT34201-1 unless otherwise noted.
Output Voltage in Refresh Mode,
LT3420
335
330
325
320
V
OUT
(V)
V
OUT
(V)
TIME (s)
315
310
305
300
295
–50 –25
0
25
FIGURE 1 CIRCUIT
V
CC
= 3.3V
V
BAT
= 3.3V
50
75
100
125
TEMPERATURE (°C)
3420 G01
U W
Output Voltage in Refresh Mode,
LT3420
335
330
8
325
320
315
310
305
300
295
2.5
3.0
3.5
4.0
FIGURE 1 CIRCUIT
V
CC
= V
IN
V
BAT
= V
IN
T
A
= 25°C
4.5
5.0
5.5
6.0
V
IN
(V)
3420 G02
Charge Time, LT3420
10
FIGURE 1 CIRCUIT
UNLESS OTHERWISE
NOTED.
V
OUT
CHARGED
FROM
50V TO 320V
T
A
= 25°C
6
C
OUT
= 220µF
4
C
OUT
= 100µF
2
0
2
3
4
V
BAT
(V)
3420 G03
5
6
3420fa
3
LINER [ LINEAR TECHNOLOGY ]
