LT3518
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Note 2) VIN = 5V, SHDN = 5V, PWM = 5V unless otherwise noted.
PARAMETER
Minimum V Operating Voltage
CONDITIONS
MIN
TYP
MAX
UNITS
3
V
V
IN
Maximum V Operating Voltage
Continuous Operation (Note 3)
30
96
IN
l
Current Sense Voltage (V – V
)
ISN
V
V
= 2V, V = 24V, V = 1V
100
100
103
mV
mV
ISP
CTRL
CTRL
ISP
C
= 2V, V = 0V, V = 1V
ISP
C
10% Scale Current Sense Voltage (V – V
)
ISN
V
= 100mV, V = 24V, V = 1V
9
mV
ISP
CTRL
ISP
C
Current Sense Voltage Line Regulation
2V < V < 45V
0.03
%/V
ISP
V
IN
Supply Current
PWM > 1.5V, V = 0V
6
4.5
0.1
10
1
mA
mA
μA
C
PWM = 0V
SHDN = 0V
l
Switching Frequency
R = 16.7k
0.85
2.25
220
1.0
2.5
250
1.15
2.7
270
MHz
MHz
kHz
T
R = 4.03k
T
R = 91.5k
T
R Voltage
1
9
V
μA
μA
V
T
Soft-Start Pin Current
SYNC Pull-Down Current (Into the Pin)
SYNC Input Low
SS = 0.5V, Out of Pin
6
12
V
SYNC
= 2V
60
0.4
SYNC Input High
1.5
V
Maximum Duty Cycle
R = 91.5k (250kHz)
95
94
85
97
96
90
74
%
%
%
%
T
SYNC = 300kHz Clock Signal, R = 91.5k
T
l
R = 16.7k (1MHz)
T
R = 4.03k (2.5MHz)
T
Switch Current Limit
2.3
2.8
3.5
A
mV
μA
nA
μS
kΩ
nA
nA
V
Switch V
I
= 1.5A
SW
400
CESAT
Switch Leakage Current
V
= 45V, PWM = 0V
2
SW
CTRL Input Bias Current
Current Out of Pin, V
= 0.1V
20
550
1000
0
100
CTRL
Error Amplifier Transconductance
V Output Impedance
C
V Idle Input Bias Current
C
PWM = 0, V = 1V
–20
20
C
FB Pin Input Bias Current
FB Pin Threshold
Current Out of Pin, V = 0.5V
20
100
1.04
300
FB
l
0.98
1.01
ISP, ISN Idle Input Bias Current
ISP, ISN Full-Scale Input Bias Current
SHDN Voltage High
PWM = 0V
nA
μA
V
ISP Tied to ISN, V = 24V, V
= 2V
20
60
60
ISP
CTRL
1.5
1.5
SHDN Voltage Low
0.4
V
SHDN Pin Bias Current
PWM Input High Voltage
PWM Input Low Voltage
PWM Pin Bias Current
TGEN Input High Voltage
TGEN Input Low Voltage
TGEN Pin Bias Current
100
μA
V
0.4
V
120
μA
V
1.5
0.4
200
2.04
V
TGEN = 5V
100
2
μA
V
l
V
REF
Pin Voltage
I
= –100μA
1.96
REF
3518fb
3
Linear [ Linear ]
