lt3680 Linear Technology Corporation, lt3680 Datasheet - Page 6

• Manufacturer Part Number: lt3680
• Description: 36v, 3.5a, 2.4mhz Step-down Switching Regulator With 75?a Quiescent Current
• Manufacturer: Linear Technology Corporation

LT3680
TYPICAL PERFOR A CE CHARACTERISTICS
6
2.50
2.00
1.50
1.00
0.50
–10
–20
–30
–40
–50
50
40
30
20
10
0
0
–200
–50
V
Error Amp Output Current
C
Voltages
–25
CURRENT LIMIT CLAMP
SWITCHING THRESHOLD
FB PIN ERROR VOLTAGE (mV)
–100
0
10mV/DIV
0.2A/DIV
TEMPERATURE (°C)
5V/DIV
25
V
V
OUT
SW
I
L
50
Switching Waveforms; Transition
from Burst Mode to Full Frequency
V
V
I
0
LOAD
IN
OUT
= 12V
75
= 3.3V
= 110mA
W
100
100
125
3680 G19
3680 G22
1μs/DIV
U
150
200
5.0
4.5
4.0
3.5
3.0
2.5
2.0
95
90
85
80
75
–50
Power Good Threshold
Minimum Input Voltage
1
V
T
L = 4.7μH
f = 800kHz
3680 G25
OUT
A
–25
= 25°C
= 3.3V
10
0
LOAD CURRENT (mA)
TEMPERATURE (°C)
25
100
50
75
10mV/DIV
0.5A/DIV
5V/DIV
1000
100
V
V
OUT
SW
I
L
125
T
3680 G23
Switching Waveforms; Full
Frequency Continuous Operation
V
V
I
3680 G20
LOAD
A
IN
OUT
10000
150
= 25°C unless otherwise noted.
= 12V
= 3.3V
= 1A
10mV/DIV
0.2A/DIV
5V/DIV
V
V
OUT
SW
6.5
6.0
5.5
5.0
4.5
4.0
I
L
1μs/DIV
Minimum Input Voltage
Switching Waveforms; Burst Mode
V
V
I
1
LOAD
IN
OUT
V
T
L = 4.7μH
f = 800kHz
OUT
A
= 12V
= 25 °C
= 3.3V
= 10mA
= 5V
10
LOAD CURRENT (mA)
5μs/DIV
3680 G26
100
1000
3680 G21
3680 G24
3680f
10000