LT3420/LT3420-1
ABSOLUTE
(Note 1)
AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
R
REF
V
BAT
R
FB
V
CC
GND
1
2
3
4
5
10
9
8
7
6
C
T
CHARGE
DONE
SEC
SW
V
CC
Voltage .............................................................. 16V
V
BAT
Voltage ............................................................ 16V
SW Voltage (Note 2)
LT3420 ................................................................ 38V
LT3420-1 ............................................................ 50V
SEC Current ......................................................
±200mA
R
FB
Current ...........................................................
±3mA
R
REF
Voltage ........................................................... 2.5V
CHARGE Voltage ...................................................... 16V
CT Voltage .............................................................. 1.5V
DONE Voltage .......................................................... 16V
Current into DONE Pin ..........................................
±1mA
Maximum Junction Temperature .......................... 125°C
Operating Ambient Temperature Range
(Note 3) .............................................. – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
LT3420EMS
LT3420EMS-1
MS PART MARKING
LTYH
LTAJG
MS10 PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 125°C,
θ
JA
= 100°C/W,
θ
JC
= 45°C/W
(4-LAYER BOARD)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
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
Minimum Operating Voltage, V
CC
Maximum Operating Voltage, V
CC
V
CC
UVLO Hysteresis
Minimum V
BAT
Voltage
Maximum V
BAT
Voltage
V
BAT
UVLO Hysteresis
R
REF
Threshold Voltage
q
ELECTRICAL CHARACTERISTICS
CONDITIONS
q
MIN
TYP
2.2
40
1.6
275
MAX
2.5
16
1.8
16
UNITS
V
V
mV
V
V
mV
V
V
µA
µA
µA
A
A
mA
mA
ns
ns
0.98
0.975
1.00
2
90
0.01
1.02
1.025
4
130
1
1.60
1.05
50
25
R
REF
Pin Bias Current
Quiescent Current
Quiescent Current in Shutdown
Primary Side Current Limit
Secondary Side Current Limit
Leakage Blanking Pulse Width
Refresh Timer Charge/Discharge Current
Refresh Timer Upper Threshold
Refresh Timer Lower Threshold
V
RREF
= 0V, Switching
V
RFB
= V
BAT
– 0.2V (Note 4)
V
RREF
= 1.1V, Not Switching
V
CHARGE
= 0V, V
IN
= 3.3V
LT3420 (Note 5)
LT3420-1 (Note 5)
LT3420 (Note 5)
LT3420-1 (Note 5)
LT3420
LT3420-1
V
CT
= 0.75V
1.5
0.9
0.45
1.20
0.75
20
5
1.4
0.9
40
15
200
0
2.5
1.0
0.5
3.5
1.1
0.55
3420fa
2
U
µA
V
V
W
U
U
W W
W
LINER [ LINEAR TECHNOLOGY ]
