Datasheet

LT3980
5
3980fa
For more information www.linear.com/LT3980
RUN/SS PIN VOLTAGE (V)
0
SWITCH CURRENT LIMIT (A)
1.5
3980 G17
4
2
0.5 1 2
1
0
7
6
5
3
2.5 3 3.5
FB PIN VOLTAGE (mV)
0
SWITCHING FREQUENCY (kHz)
800
1000
1200
600
3980 G14
600
400
200 400
800
500
100 300
700 900
200
0
TEMPERATURE (°C)
MINIMUM SWITCH ON-TIME (ns)
180
200
220
3980 G16
160
140
120
100
240
–50 25–25 0 50 75 100 150125
I
LOAD
= 1A
RUN/SS PIN VOLTAGE (V)
RUN/SS PIN CURRENT (µA)
16
20
24
3980 G18
12
8
4
0
0 10 20 30 40 50 60
SWITCH CURRENT (A)
0
BOOST PIN CURRENT (mA)
15
45
60
75
120
3980 G11
30
90
105
0 31 2
TEMPERATURE (°C)
FEEDBACK VOLTAGE (mV)
800
3980 G12
760
840
780
820
–50 25–25 0 50 75 100 150125
TEMPERATURE (°C)
FREQUENCY (MHz)
1.00
1.10
3880 G13
0.90
0.80
1.20
0.95
1.05
0.85
1.15
–50 25–25 0 50 75 100 150125
RF = 32.4k
SWITCH CURRENT (A)
0
400
500
700
3
3980 G10
300
200
1 2
100
0
600
VOLTAGE DROP (mV)
Boost Pin Current
vs Switch Current Feedback Voltage
Switching Frequency Frequency Foldback
Minimum Switch On-Time Soft-Start RUN/SS Pin Current
Switch Voltage Drop
T
A
= 25°C unless otherwise noted.
Typical perFormance characTerisTics
R
T
vs Frequency
RESISTANCE (kΩ)
1
2000
SWITCHING FREQUENCY (kHz)
2500
3000
10 100 1000
1500
1000
500
0
3500
3980 G15
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