LT1725
ABSOLUTE
(Note 1)
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
PGND 1
I
SENSE
2
SFST 3
R
OCMP
4
R
CMPC
5
OSCAP 6
V
C
7
FB 8
16 GATE
15 V
CC
14 t
ON
13 ENDLY
12 MINENAB
11 SGND
10 UVLO
9
3V
OUT
V
CC
Supply Voltage ................................................. 22V
UVLO Pin Voltage .................................................... V
CC
I
SENSE
Pin Voltage .................................................... 2V
FB Pin Current .....................................................
±2mA
Operating Junction
Temperature Range
LT1725C .............................................. 0°C to 100°C
LT1725I ........................................... –40°C TO 125°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................ 300°C
ORDER PART
NUMBER
LT1725CGN
LT1725CS
LT1725IGN
LT1725IS
GN PART
MARKING
1725
1725I
GN PACKAGE
S PACKAGE
16-LEAD PLASTIC SSOP 16-LEAD PLASTIC SO
T
JMAX
= 125°C,
θ
JA
= 110°C/W (GN)
T
JMAX
= 125°C,
θ
JA
= 100°C/W (SO)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
SYMBOL
Power Supply
V
CC
V
CC
Turn-On Voltage
V
CC
Turn-Off Voltage
V
CC
Hysteresis (Note 3)
Supply Current
Start-Up Current
Feedback Voltage
PARAMETER
The
q
denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 14V, GATE open, V
C
= 1.4V unless otherwise noted.
CONDITIONS
q
q
q
q
q
MIN
14.0
8
4.0
6
TYP
15.1
9.7
5.4
10
120
1.245
500
MAX
16.0
11
6.5
15
280
1.260
1.270
1800
80
0.05
50
UNITS
V
V
V
mA
µA
V
V
nA
µmho
µA
V
%/V
V/V
µA
mA
V
V
(V
TURN-ON
– V
TURN-OFF
)
V
C
= Open
I
CC
Feedback Amplifier
V
FB
I
FB
g
m
I
SRC
, I
SNK
V
CL
q
1.230
1.220
400
30
Feedback Pin Input Current
Feedback Amplifier Transconductance
Feedback Amplifier Source or Sink Current
Feedback Amplifier Clamp Voltage
Reference Voltage/Current Line Regulation
Voltage Gain
Soft-Start Charging Current
Soft-Start Discharge Current
12V
≤
V
IN
≤
18V
V
C
= 1V to 2V
V
SFST
= 0V
V
SFST
= 1.5V, V
UVLO
= 0V
I
GATE
= 100mA
I
GATE
= 500mA
I
GATE
= 100mA
I
GATE
= 500mA
V
GATE
= 2V
C
L
= 1000pF
C
L
= 1000pF
q
q
q
q
q
q
∆l
C
=
±10µA
q
q
1000
50
2.5
0.01
2000
25
0.8
11.5
11.0
40
1.5
12.1
11.8
0.3
0.6
Gate Output
V
GATE
Output High Level
Output Low Level
I
GATE
t
r
t
f
Output Sink Current in Shutdown, V
UVLO
= 0V
Rise Time
Fall Time
0.45
1.0
1.2
2.5
30
30
2
U
V
V
mA
ns
ns
1725f
W
U
U
W W
W
LINER [ LINEAR TECHNOLOGY ]
