LT1949 LINER [Linear Technology], LT1949 Datasheet - Page 3

• Manufacturer Part Number: LT1949
• Description: 600kHz, 1A Switch PWM DC/DC Converter
• Manufacturer: LINER [Linear Technology]

ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LT1949E is 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.
temperature range, otherwise specifications are T
SYMBOL
TYPICAL PERFOR A CE CHARACTERISTICS
700
650
600
550
500
1.0
0.8
0.6
0.4
0.2
0
0
0
Oscillator Frequency
Switch Voltage Drop (V
0.2
PARAMETER
Switch V
Reference Line Regulation
SHDN Input Voltage High
SHDN Input Voltage Low
2
25 C
85 C
SWITCH CURRENT (A)
0.4
4
INPUT VOLTAGE
–40 C
CESAT
0.6
6
25 C
0.8
8
CESAT
–40 C
W
85 C
10
1.0
)
1949 G01
1949 G04
U
1.2
12
1.25
1.24
1.23
1.22
1.21
1.20
1.3
1.2
1.1
1.0
0.9
0.8
A
–50
= 25 C. V
0
Feedback Voltage
Switch Current Limit
–25
CONDITIONS
I
I
1.8V V
20
SW
SW
The
IN
= 800mA
= 500mA
TEMPERATURE ( C)
0
= 2V, V
DUTY CYCLE (%)
40
IN
denotes specifications which apply over the full operating
25
12V
Note 3: Bias current flows into FB pin.
Note 4: Switch current limit guaranteed by design and/or correlation to
static tests. Duty cycle affects current limit due to ramp generator.
Note 5: Bias current flows out of LBI pin.
SHDN
60
50
= 2V unless otherwise noted.
80
75
1949 G05
1949 G02
100
100
1.3
1.2
1.1
1.0
0.9
0.8
4.6
4.5
4.4
4.3
4.2
4.1
4.0
3.9
3.8
–50
–50
MIN
1.4
Switch Current Limit,
Duty Cycle = 30%
Quiescent Current, SHDN = 2V
–25
–25
TEMPERATURE ( C)
TEMPERATURE ( C)
TYP
0.08
410
0
0
25
25
MAX
0.15
LT1949
400
50
50
0.4
6
75
75
1949 G03
1949 G06
UNITS
3
%/V
mV
mV
100
100
V
V