Datasheet

LT3688
5
3688f
TYPICAL PERFORMANCE CHARACTERISTICS
No-Load Supply Current (Input)
No-Load Supply Current
(Temperature)
Maximum Load Current (5V)
Maximum Load Current (3.3V)
Switch Current Limit
vs Duty Cycle
Switch Current Limit
vs Temperature
T
A
= 25°C unless otherwise noted.
V
IN
(V)
0 10203040
0
SUPPLY CURRENT (µA)
120
140
100
40
60
20
80
160
3688 G04
V
OUT1
= 5V
V
OUT2
= 3.3V
INPUT VOLTAGE (V)
010203040
0
LOAD CURRENT (A)
1.5
0.5
1
2
3688 G06
L = 15µH
L = 10µH
f
SW
= 1MHz
INPUT VOLTAGE (V)
f
SW
= 1MHz
0 10203040
0
LOAD CURRENT (A)
1.5
0.5
1
2
3688 G07
L = 15µH
L = 10µH
DUTY CYCLE (%)
0 20406080100
0
CURRENT LIMIT (A)
1.4
0.2
0.4
0.6
1
1.2
1.6
0.8
1.8
3688 G08
TYPICAL
MIN
TEMPERATURE (°C)
–50 –25 0 50 7525 100 125 150
0
CURRENT LIMIT (A)
0.5
1.0
1.5
2.0
3688 G09
DC = 15%
Switch Voltage Drop
BST Pin Current
Feedback Voltage
SWITCH CURRENT (mA)
0 200 400 800600 1000
0
SWITCH VOLTAGE (mV)
50
100
150
250
300
200
350
3688 G10
SWITCH CURRENT (mA)
0 200 400 800600 1000
0
BST PIN CURRENT (mA)
5
15
20
10
25
3688 G11
TEMPERATURE (°C)
–50 –20 25 500 100 12575 150
0.790
FEEDBACK VOLTAGE (V)
0.795
0.805
0.800
0.810
3688 G12
TEMPERATURE (°C)
–50 –25 0 25 50 75 100 125 150
0
SUPPLY CURRENT (µA)
2500
1000
1500
500
2000
3000
3688 G05
CATCH DIODE: B140HB
V
IN
= 12V
V
OUT1
= 5V
V
OUT2
= 3.3V
INCREASED SUPPLY
CURRENT DUE TO CATCH
DIODE LEAKAGE AT HIGH
TEMPERATURE