LTC3240-3.3_15 Datasheet, PDF (4/12 Pages) Linear Technology – 3.3V/2.5V Step-Up/ Step-Down Charge Pump DC/DC Converter

LTC3240-3.3/LTC3240-2.5
TYPICAL PERFOR A CE CHARACTERISTICS ^(TA ^{= 25°C, C}FLY ^{= C}IN ^{= 1µF, C}OUT ^{= 4.7µF}
unless otherwise noted)
Effective Open-Loop Resistance
vs Temperature (LTC3240-3.3)
10
V_IN = 1.8V
V_OUT = 3V
9
8
7
6
5
–40 –15 10
35
60
85
TEMPERATURE (°C)
3240 G07
No-Load Input Current
vs Supply Voltage (LTC3240-3.3)
100
90
80
70
60
50
40
30
20
10
0
1.7 2.2 2.7 3.2 3.7 4.2 4.7 5.2 5.7
SUPPLY VOLTAGE (V)
3240 G08
No-Load Input Current
vs Supply Voltage (LTC3240-2.5)
100
90
80
70
60
50
40
30
20
10
0
1.7 2.2 2.7 3.2 3.7 4.2 4.7 5.2 5.7
SUPPLY VOLTAGE (V)
3240 G09
Mode Switch Threshold
vs Load Current (LTC3240-3.3)
3.80
DOUBLER TO
3.75
LDO MODE
(V_IN RISING)
3.70
3.65
3.60
LDO TO
3.55
DOUBLER MODE
(V_IN FALLING)
3.50
3.45
3.40
0
20 40 60 80 100 120 140 160
I_LOAD (mA)
3240 G10
Mode Switch Threshold
vs Load Current (LTC3240-2.5)
2.95
2.90
2.85
DOUBLER TO LDO
MODE (V_IN RISING)
2.80
2.75
LDO TO DOUBLER
MODE (V_IN FALLING)
2.70
2.65
0
20 40 60 80 100 120 140 160
I_LOAD (mA)
3240 G11
Efficiency vs Supply Voltage
(LTC3240-3.3)
100
LDO TO DOUBLER
90
MODE (V_IN FALLING)
80
I_LOAD = 40mA
70
60
I_LOAD = 1mA
50
40
DOUBLER TO LDO
30
MODE (V_IN RISING)
20
10
0
1.80 2.30 2.80 3.30 3.80 4.30 4.80 5.30 5.80
SUPPLY VOLTAGE (V)
3240 G12
V_OUT Soft-Start (LTC3240-3.3)
Output Noise/Ripple
(LTC3240-3.3)
V_OUT
2V/DIV
SHDN
2V/DIV
V_IN = 2.4V
R_LOAD = 66Ω
200µs/DIV
3240 G13
V_OUT
20mV/DIV
AC COUPLED
V_IN = 2.4V
500ns/DIV
I_LOAD = 100mA
3240 G14
3240fb
4