LTC3785 LINER [Linear Technology], LTC3785 Datasheet - Page 7

• Manufacturer Part Number: LTC3785
• Description: High Efficiency, Synchronous, 4-Switch Buck-Boost Controller
• Manufacturer: LINER [Linear Technology]

Typical perForMance characTerisTics
200mV/DIV
2A/DIV
–200
–100
–150
150
140
130
120
110
100
V
200
150
100
–50
90
80
70
60
50
OUT
50
0
I
L
0
Maximum Current Sense
Threshold vs Duty Factor (Boost)
0
Peak Current Threshold
vs V
Load Step
V
V
LOAD STEP = 200mA TO 2A
IN
OUT
= 6V
ITH
= 12V
0.5
20
(Boost)
DUTY FACTOR (%)
1
40
400µs/DIV
V
ITH
1.5
(V)
60
2
80
2.5
3789 G25
3789 G19
3789 G22
100
3
200mV/DIV
2A/DIV
–100
V
150
140
130
120
110
100
200
150
100
–50
90
80
50
OUT
70
60
50
0
I
L
0
Maximum Current Sense
Threshold vs Duty Factor (Buck)
0
Valley Current Threshold
vs V
V
V
LOAD STEP = 300mA TO 3A
Load Step
IN
OUT
= 12V
ITH
= 12V
20
0.5
(Buck)
DUTY FACTOR (%)
40
400µs/DIV
1
V
ITH
(V)
60
1.5
80
2
T
A
3789 G26
= 25°C unless otherwise noted.
3789 G20
3789 G23
100
2.5
200mV/DIV
2A/DIV
V
140
120
110
100
150
130
160
120
100
140
OUT
90
80
70
60
80
60
40
20
0
I
–50
L
0
Maximum Current Limit
vs Temperature
Current Foldback Limit
Load Step
V
V
LOAD STEP = 300mA TO 3A
IN
OUT
–30
0.1
= 18V
= 12V
–10
0.2
TEMPERATURE (°C)
10
0.3
400µs/DIV
BOOST
30
0.4
V
BUCK
LTC3789
FB
(V)
50
0.5
70
0.6
90
0.7
110
0.8
3789 G24
3789 G27
7
3789 G21
3789f
130
0.9