LTC3240-3.3_15 Datasheet, PDF (3/12 Pages) Linear Technology – 3.3V/2.5V Step-Up/ Step-Down Charge Pump DC/DC Converter

LTC3240-3.3/LTC3240-2.5
ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C, ^⎯S^⎯H^⎯D^⎯N = V_IN, C_FLY = 1µF, C_IN = 1µF, C_OUT = 4.7µF unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
R_OL
Effective Open-Loop
Output Resistance
Doubler Mode
LTC3240-3.3
LTC3240-2.5
(Note 3)
V_IN = 1.8V, V_OUT = 3V
V_IN = 1.8V, V_OUT = 2.25V
7.5
Ω
8.0
Ω
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3240-3.3/LTC3240-2.5 are guaranteed to meet
performance specifications from 0°C to 85°C. Specifications over the
–40°C to 85°C operating temperature range are assured by design,
characterization and correlation with statistical process controls.
Note 3: R_OL ≡ (2V_IN – V_OUT)/I_OUT
Note 4: Failure to solder the exposed backside of the package to a PCB
ground plane will result in a thermal resistance much higher than 80°C/W.
TYPICAL PERFOR A CE CHARACTERISTICS (T_A = 25°C, C_FLY = C_IN = 1µF, C_OUT = 4.7µF
unless otherwise noted)
Oscillator Frequency vs Supply
Voltage (Doubler Mode)
1.8
1.6
1.4
25°C ^{–40°C}
1.2
85°C
1.0
0.8
0.6
1.8
2.2
2.6
3.0
3.4
3.8
SUPPLY VOLTAGE (V)
3240 G01
Start-Up Time vs Supply Voltage
1000
I_LOAD = 50mA
900
800
700
600
500
400
1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6
V_IN (V)
3240 G04
⎯S⎯H⎯D⎯N Threshold Voltage
vs Supply Voltage
1.0
25°C ^{–40°C}
0.8
85°C
0.6
0.4
0.2
SHUTDOWN
HYSTERESIS
0
1.80 2.30 2.80 3.30 3.80 4.30 4.80 5.30 5.80
SUPPLY VOLTAGE (V)
3240 G02
Load Regulation (LTC3240-3.3)
3.40
Short-Circuit Current
vs Supply Voltage
700
600
500
400
300
200
100
0
1.7 2.2 2.7 3.2 3.7 4.2 4.7 5.2 5.7
SUPPLY VOLTAGE (V)
3240 G03
Load Regulation (LTC3240-2.5)
2.60
3.35
V_IN = 3.7V
3.30
V_IN = 2.5V
3.25
V_IN = 1.8V
3.20
0
30
60
90 120 150
LOAD CURRENT (mA)
3240 G05
2.55
V_IN = 2.8V
2.50
V_IN = 1.8V
V_IN = 2.4V
2.45
2.40
0
30
60
90 120 150
LOAD CURRENT (mA)
3240 G06
3240fb
3