LTC3251_15 Datasheet, PDF (5/16 Pages) Linear Technology – 500mA High Efficiency, Low Noise, Inductorless Step-Down DC/DC Converter

LTC3251/
LTC3251-1.2/LTC3251-1.5
TYPICAL PERFOR A CE CHARACTERISTICS
MD0/MD1 Input Threshold Voltage
vs Supply Voltage
1.2
1.1
1.0
–40°C
0.9
25°C
0.8
85°C
0.7
0.6
0.5
0.4
2.7 3.2 3.7 4.2 4.7 5.2
V_IN (V)
3251 G10
Output Transient Response
(Continuous Mode)
450mA
I_OUT
50mA
Max/Min Oscillator Frequency
vs Supply Voltage
2.0
1.9
1.8
1.7
–40°C MAX ^{25°C MAX}
1.6
1.5
85°C MAX
1.4
1.3
1.2
25°C MIN
1.1
–40°C MIN
1.0
0.9
85°C MIN
0.8
2.7 3.2 3.7 4.2 4.7 5.2
V_IN (V)
3251 G11
Output Transient Response
(Burst Mode Operation)
450mA
I_OUT
50mA
V_IN
V_OUT
20mV/DIV
(AC)
V_OUT
20mV/DIV
(AC)
V_OUT
20mV/DIV
(AC)
T_A = 25°C
10µs/DIV
C_OUT = 10µF X5R 6.3V
V_OUT = 1.5V
3251 G13
T_A = 25°C
10µs/DIV
C_OUT = 10µF X5R 6.3V
V_OUT = 1.5V
3251 G14
Supply Transient Response
(Continuous Mode)
4.5V
V_IN
3.5V
V_OUT
20mV/DIV (AC)
T_A = 25°C
20µs/DIV
C_OUT = 10µF X5R 6.3V
I_OUT = 250mA
V_OUT = 1.5V
3251 G15
LTC3251-1.5 Output Voltage
Ripple
SPREAD
SPECT
ENABLED
10mV/DIV (AC)
SPREAD
SPECT
DISABLED
10mV/DIV (AC)
T_A = 25°C
200ns/DIV
C_OUT = 10µF X5R 6.3V
I_OUT = 500mA
V_OUT = 1.5V
3251 G16
32511215fb
5