Datasheet

5
LTC3251/
LTC3251-1.2/LTC3251-1.5
32511215fb
TYPICAL PERFOR A CE CHARACTERISTICS
UW
MD0/MD1 Input Threshold Voltage
vs Supply Voltage
Max/Min Oscillator Frequency
vs Supply Voltage
V
IN
(V)
2.7
1.2
1.0
0.8
85°C
–40°C
0.6
1.1
0.9
0.7
0.5
0.4
4.2 5.2
3251 G10
3.2 3.7
4.7
MD0/MD1 THRESHOLD (V)
25°C
V
IN
(V)
2.7
0.8
FREQUENCY (MHz)
1.0
1.2
1.4
1.6
2.0
3.2
3.7 4.2 4.7
3251 G11
5.2
1.8
0.9
1.1
1.3
1.5
1.9
1.7
–40°C MAX
–40°C MIN
25°C MAX
25°C MIN
85°C MAX
85°C MIN
Output Transient Response
(Continuous Mode)
450mA
50mA
I
OUT
V
OUT
20mV/DIV
(AC)
T
A
= 25°C10µs/DIV 3251 G13
C
OUT
= 10µF X5R 6.3V
V
OUT
= 1.5V
Output Transient Response
(Burst Mode Operation)
450mA
50mA
I
OUT
V
OUT
20mV/DIV
(AC)
T
A
= 25°C10µs/DIV 3251 G14
C
OUT
= 10µF X5R 6.3V
V
OUT
= 1.5V
Supply Transient Response
(Continuous Mode)
4.5V
3.5V
V
IN
V
OUT
20mV/DIV
(AC)
T
A
= 25°C20µs/DIV 3251 G15
C
OUT
= 10µF X5R 6.3V
I
OUT
= 250mA
V
OUT
= 1.5V
LTC3251-1.5 Output Voltage
Ripple
SPREAD
SPECT
DISABLED
10mV/DIV (AC)
SPREAD
SPECT
ENABLED
10mV/DIV (AC)
T
A
= 25°C 200ns/DIV 3251 G16
C
OUT
= 10µF X5R 6.3V
I
OUT
= 500mA
V
OUT
= 1.5V
V
OUT
20mV/DIV (AC)
V
IN