Datasheet

LTC3780
8
3780ff
For more information www.linear.com/LTC3780
Oscillator Frequency
vs Temperature
Undervoltage Reset
vs Temperature
Minimum Current Sense
Threshold vs Duty Factor (Buck)
Maximum Current Sense
Threshold vs Duty Factor (Boost)
Maximum Current Sense
Threshold vs Duty Factor (Buck)
Minimum Current Sense
Threshold vs Temperature
Peak Current Threshold
vs V
ITH
(Boost)
Valley Current Threshold
vs V
ITH
(Buck)
Current Foldback Limit
Typical perForMance characTerisTics
TEMPERATURE (°C)
–75 –50
0
FREQUENCY (kHz)
50
150
200
250
50
450
3780 G19
100
0
–25
75 100
25 125
300
350
400
V
PLLFLTR
= 2.4V
V
PLLFLTR
= 1.2V
V
PLLFLTR
= 0V
TEMPERATURE (°C)
–75 –50 –25
3.0
UNDERVOLTAGE RESET (V)
3.4
4.2
4.0
0
50
75
3780 G20
3.2
3.8
3.6
25
100
125
DUTY FACTOR (%)
–80
I
SENSE
+
(mV)
–60
–40
–20
80 60 40 20
3780 G21
0100
DUTY FACTOR (%)
0
I
SENSE
+
(mV)
140
160
80
3780 G22
120
100
20
40
60
100
180
DUTY FACTOR (%)
110
I
SNESE
+
(mV)
120
130
140
20 40 60 80
3780 G23
1000
TEMPERATURE (°C)
–75 –50
50
100
200
25 75
3780 G24
0
–50
–25 0
50 100 125
–100
–150
150
MAXIMUM I
SNESE
+
THRESHOLD (mV)
BOOST
BUCK
V
ITH
(V)
0
–100
I
SENSE
+
(mV)
–50
0
50
100
200
0.4
0.8 1.2 1.6
3780 G25
1.8 2.4
150
V
ITH
(V)
0
–150
I
SENSE
+
(mV)
–100
–50
0
50
100
0.4
0.8 1.2 1.6
3780 G26
2.0 2.4
V
OSENSE
(V)
0
0
I
SENSE
+
(mV)
40
80
120
160
200
BUCK
BOOST
0.2 0.4 0.6
3780 G32
0.8
T
A
= 25°C, unless otherwise noted.