LTC3569_15 Datasheet, PDF (5/26 Pages) Linear Technology – Triple Buck Regulator with 1.2A and Two 600mA Outputs and Individual Programmable References

LTC3569
Typical Performance Characteristics T_A = 25°C, unless otherwise noted.
Efficiency vs V_SUPPLY
OUT1 = 1.8V
95
90
BUCK1 ONLY
85
80
75
I_LOAD = 270mA
70
I_LOAD = 220mA
I_LOAD = 170mA
I_LOAD = 120mA
65
2
3
4
5
6
V_SUPPLY (V)
3569 G04
Efficiency vs V_SUPPLY
OUT2 = 1.2V
95
90
BUCK2 ONLY
85
80
75
70
65
2
I_LOAD = 210mA
I_LOAD = 170mA
I_LOAD = 110mA
I_LOAD = 70mA
3
4
5
V_SUPPLY (V)
6
3569 G05
Efficiency vs V_SUPPLY
OUT3 = 1.5V
95
90
BUCK3 ONLY
85
80
75
70
65
2
I_LOAD = 210mA
I_LOAD = 170mA
I_LOAD = 110mA
I_LOAD = 70mA
3
4
5
V_SUPPLY (V)
6
3569 G06
Oscillator Frequency
vs Temperature
2.40
V_IN = 5.5V
2.30
V_IN = 3.5V
2.20
V_IN = 2.5V
2.10
V_RT = SV_IN
2.00
–50
0
50
100
TEMPERATURE (°C)
150
3569 G07
R_DS(ON) SW1
vs V_SUPPLY and Temperature
0.35
NSW1
100°C
PSW1
0.30
25°C
0.25
0.20
0.15 _{–50°C}
0.10
2
3
4
5
V_SUPPLY (V)
6
3569 G08
V_FB vs Temperature
0.3
V_REF SET TO MAX
0.2
0.1
0.0
–0.1
–0.2
–0.3
–50
0
50
100
TEMPERATURE (°C)
V_FB1
V_FB2
V_FB3
150
3569 G10
I_SVIN vs V_SUPPLY Pulse-Skipping
700
600
ALL 3
500
2 BUCKS ENABLED
400
300
1 BUCK ENABLED
200
100
0
2
NO LOAD
3
4
5
V_SUPPLY (V)
6
3569 G11
For more information www.linear.com/LTC3569
R_DS(ON) SW2 and SW3
vs V_SUPPLY and Temperature
0.50
100°C
0.45
NSW2 & 3
PSW3 & 3
0.40 _25°C
0.35
0.30
0.25
–50°C
0.20
0.15
0.10
2
3
4
5
V_SUPPLY (V)
6
3569 G09
I_SVIN
vs V_SUPPLY Burst Mode Operation
120
100
ALL 3
80
2 BUCKS ENABLED
60
1 BUCK ENABLED
40
20
0
2
NO LOAD
3
4
5
V_SUPPLY (V)
6
3569 G12
3569fe
5