Datasheet

LT3681
6
3681f
TEMPERATURE (°C)
–50
THRESHOLD VOLTAGE (V)
1.50
2.00
2.50
25 75 125
3681 G22
1.00
0.50
0
–25 0 50 100
CURRENT LIMIT CLAMP
SWITCHING THRESHOLD
V
C
Voltages
3681 G24
I
L
0.5A/DIV
V
SW
5V/DIV
V
OUT
10mV/DIV
2µs/DIV
V
IN
= 12V; FRONT PAGE APPLICATION
I
LOAD
= 10mA
FB PIN VOLTAGE (V)
1.065
–80
V
C
PIN CURRENT (µA)
–60
–20
0
20
1 .265 1.465
100
3681 G19
–40
1.165 1.365
40
60
80
LOAD CURRENT (A)
0.001
INPUT VOLTAGE (V)
3.0
3.5
10
3681 G20
2.5
2.0
0.01
0.1
1
4.5
4.0
V
OUT
= 3.3V
L = 4.7
f = 800kHz
LOAD CURRENT (A)
0.001
INPUT VOLTAGE (V)
5.0
5.5
10
3681 G20
4.5
4.0
0.01
0.1
1
6.5
6.0
V
OUT
= 5.0V
L = 4.7
f = 800kHz
TEMPERATURE (°C)
–50
THRESHOLD VOLTAGE (V)
1.160
1.180
1.200
25 75 125
3681 G23
1.140
1.120
1.100
–25 0 50 100
PG RISING
3681 G25
I
L
0.5A/DIV
V
RUN/SS
5V/DIV
V
OUT
10mV/DIV
V
IN
= 12V; FRONT PAGE APPLICATION
I
LOAD
= 140mA
1µs/DIV
3681 G26
I
L
0.5A/DIV
V
RUN/SS
5V/DIV
V
OUT
10mV/DIV
V
IN
= 12V; FRONT PAGE APPLICATION
I
LOAD
= 1A
1µs/DIV
Error Amp Output Current
Minimum Input Voltage
Minimum Input Voltage
Power Good Threshold
Switching Waveforms; Transition
from Burst Mode to Full
Frequency
Switching Waveforms; Full
Frequency Continuous Operation
Switching Waveforms;
Burst Mode
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Power Schottky Diode Forward
Voltage vs Current
FORWARD VOLTAGE (V)
0
CURRENT (mA)
0.2
3681 G29
3000
0.1 0.3
1000
0
6000
5000
4000
2000
0.4 0.5 0.6 0.7
T
A
= 25°C unless otherwise noted.