LT1109
W W W
U
ABSOLUTE AXI U RATI GS
(Voltages Referred to GND Pin)
Supply Voltage (VOUT) .............................. –0.4V to 20V
SW Pin Voltage..........................................–0.4V to 50V
SHUTDOWN Pin Voltage......................................... 6.0V
Operating Temperature Range ..................... 0°C to 70°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec.)................. 300°C
Maximum Power Dissipation ............................. 300mW Switch Current........................................................ 1.2A
W U
/O
PACKAGE RDER I FOR ATIO
BOTTOM VIEW
TOP VIEW
TOP VIEW
3
2
1
1
2
3
4
8
7
6
5
SENSE
SHUTDOWN
NC
V
VIN
NC
1
2
3
4
SENSE
SHUTDOWN
NC
8
7
6
5
IN
V
GND
SW
OUT
NC
SW
SW
GND
NC
NC
GND
Z PACKAGE
3-LEAD TO-92 PLASTIC LT1109 • POI01
S8 PACKAGE
8-LEAD PLASTIC SOIC
N8 PACKAGE
8-LEAD PLASTIC DIP
LT1109 • PO103
LT1109 • PO102
TJMAX = 100°C, θJA = 150°C/W
TJMAX = 100°C, θJA = 130°C/W
T
JMAX = 100°C, θJA = 160°C/W
S8 PART
MARKING
ORDER PART
NUMBER
ORDER PART
NUMBER
ORDER PART
NUMBER
LT1109CS8
LT1109CS8-5
LT1109CS8-12
LT1109CN8
LT1109CN8-5
LT1109CN8-12
1109
10905
10912
LT1109CZ-5
LT1109CZ-12
ELECTRICAL CHARACTERISTICS TA = 25°C, VIN = 3V (LT1109CN8, LT1109CS8), unless otherwise specified.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
µA
I
Quiescent Current
Switch Off
●
320
550
Q
Minimum Start-Up Voltage
1.6
V
at V
Pin (Z Package)
OUT
V
V
Input Voltage (N8, S8 Package)
Comparative Trip Point Voltage
Output Voltage
●
●
3
V
V
IN
LT1109
1.20
1.25
1.30
LT1109-5; 3V ≤ V ≤ 5V
LT1109-12; 3V ≤ V ≤ 12V
●
●
4.75
11.52
5.00
12.00
5.25
12.55
V
V
OUT
IN
IN
Comparator Hysteresis
Output Voltage Ripple
LT1109
●
8
12.5
mV
LT1109-5
LT1109-12
●
●
25
60
50
120
mV
mV
f
t
Oscillator Frequency
Switch ON Time
100
90
120
4.2
50
140
150
kHz
kHz
OSC
ON
●
3.3
3.0
5.3
5.5
µs
µs
●
●
DC
Duty Cycle
Full Load
45
60
%
V
CESAT
Switch Saturation Voltage
I
= 500mA
SW
0.4
0.5
0.7
0.8
V
V
LT1109-5: V = 3V; LT1109-12: V = 5V
●
IN
IN
2
Linear [ Linear ]
