Datasheet

LTC3646/LTC3646-1
5
36461fa
For more information www.linear.com/LTC3646
Typical perForMance characTerisTics
Efficiency vs Input Voltage,
Burst Mode Operation
Reference Voltage
vs Temperature R
DS(ON)
vs Temperature
Switch Pin Leakage
vs Temperature and Supply
Oscillator Internal Set Frequency
vs Temperature
Efficiency vs Load Current,
Burst Mode Operation
Efficiency vs Load Current,
Forced Continuous Mode Operation Efficiency vs Load Current
T
A
= 25°C, SVIN/PVIN = 12V, f
O
= 1MHz unless otherwise noted.
Oscillator Externally Set Frequency
vs Temperature
INPUT VOLTAGE (V)
0
EFFICIENCY (%)
80
90
40
36461 G04
70
60
105
100
75
85
65
95
15 20 25 30 35
LOAD = 500mA
LOAD = 100mA
LOAD = 1A
L = 6.8µH
V
OUT
= 3.3V
TEMPERATURE (°C)
–50
RESISTANCE (Ω)
0.20
0.30
150130110
36461 G06
0.10
0
–10–30
0.35
0.15
0.25
0.05
10 30 50 70 90
MAIN SWITCH
SYNCHRONOUS SWITCH
TEMPERATURE (°C)
–50
SW LEAKAGE CURRENT (µA)
14
18
150130110
36461 G07
10
0
–10–30
20
12
16
8
4
6
2
10 30 50 70 90
V
DS
= 12V, MAIN SWITCH
V
DS
= 12V, SYNCHRONOUS SWITCH
V
DS
= 40V, MAIN SWITCH
V
DS
= 40V, SYNCHRONOUS SWITCH
TEMPERATURE (°C)
–40
FREQUENCY (MHz)
2.35
2.45
140120100
36461 G08
2.25
2.00
0–20
2.50
2.30
2.40
2.20
2.10
2.15
2.05
20 40 60 80
V
RT
= V
INTVCC
TEMPERATURE (°C)
–40
FREQUENCY (MHz)
1.5
1.7
140120100
36461 G09
1.3
1.2
0–20
1.8
1.4
1.6
20 40 60 80
R
RT
= 60k
TEMPERATURE (°C)
–50
V
REF
(V)
600
604
150130110
36461 G05
596
592
–10–30
608
598
602
594
606
10 30 50 70 90
LOAD CURRENT (A)
0.001
EFFICIENCY (%)
40
60
1
36461 G01
20
0
0.1
0.01
100
30
50
10
70
80
90
V
IN
= 5V
V
IN
= 8V
V
IN
= 12V
V
OUT
= 1.8V
f
O
= 1.5MHz
LOAD CURRENT (A)
0.001
EFFICIENCY (%)
40
60
1
36461 G02
20
0
0.1
0.01
100
30
50
10
70
80
90
V
IN
= 5V
V
IN
= 8V
V
IN
= 12V
V
OUT
= 1.8V
f
O
= 1.5MHz
LOAD CURRENT (A)
0.001
EFFICIENCY (%)
40
60
1
36461 G03
20
0
0.1
0.01
100
30
50
10
70
80
90
FORCED CONTINUOUS
OPERATION
V
OUT
= 5V
V
OUT
= 3.3V
Burst Mode OPERATION