LTC3527-1_15 Datasheet, PDF (5/22 Pages) Linear Technology – Dual 800mA/400mA, 1.2MHz/2.2MHz Synchronous Step-Up DC/DC Converters

LTC3527/LTC3527-1
TYPICAL PERFORMANCE CHARACTERISTICS (T_A = 25°C, unless otherwise noted)
No-Load Input Current vs V_IN
180
1.2MHz
160
140
V_OUT = 5V
120
100
80
60
40
20 ^VOUT ⁼
1.8V
0
0.5 1 1.5
V_OUT =
2.4V
V_OUT = 3.3V
2 2.5 3 3.5 4 4.5
V_IN (V)
35271 G09
Maximum Output Current
vs V_IN for Converter 1
800
700
V_OUT =
2.5V
V_OUT = 3.3V
600
V_OUT =
1.8V
500
400
300
V_OUT = 5V
200
100
0
0.5 1 1.5 2 2.5 3 3.5 4 4.5
V_IN (V)
35271 G10
Maximum Output Current
vs V_IN for Converter 2
500
450
400
V_OUT = 3.3V
V_OUT =
350
2.5V
300
V_OUT =
1.8V
250
200
150
V_OUT = 5V
100
50
0
0.5 1 1.5 2 2.5 3 3.5
V_IN (V)
4 4.5
35271 G11
Minimum Load Resistance During
Start-Up vs V_IN
1000
CONVERTER 2
100
CONVERTER 1
Burst Mode Threshold Current
vs V_IN for V_OUT1 = V_OUT2 = 1.8V
14
2.2MHz OPERATION
12
CONVERTER 1
CONVERTER 2
10
8
LEAVE BURST
6
4
ENTER BURST
2
Burst Mode Threshold Current
vs V_IN for V_OUT1 = V_OUT2 = 3.3V
25
2.2MHz OPERATION
CONVERTER 1
20
CONVERTER 2
LEAVE
BURST
15
ENTER
BURST
10
5
10
0.635
0.685
0.735 0.785
V_IN (V)
0.835
0.885 0.935
35271 G12
0
0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5
V_IN (V)
35271 G13
0
0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0
V_IN (V)
35271 G14
Burst Mode Threshold Current
vs V_IN for V_OUT1 = V_OUT2 = 5V
70
2.2MHz OPERATION
60
CONVERTER 1
CONVERTER 2
50
LEAVE BURST
ENTER BURST
40
30
20
10
Oscillator Frequency
vs Temperature
2.50
FSEL = 3.3V
2.00
V_IN = 1.2V
V_OUT = 3.3V
1.50
FSEL = 0V
0
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
V_IN (V)
35271 G15
1.00
–45 –30 –15 0 15 30 45 60
TEMPERATURE (°C)
75 90
35271 G16
35271fc
5