lt3689-5 Linear Technology Corporation, lt3689-5 Datasheet - Page 5

• Manufacturer Part Number: lt3689-5
• Description: 700ma Step-down Regulator With Power-on Reset And Watchdog Timer
• Manufacturer: Linear Technology Corporation

TYPICAL PERFORMANCE CHARACTERISTICS
140
120
100
2.0
0.4
1.6
1.2
0.8
40
35
30
25
20
15
10
80
60
40
20
0
0
5
0
0
0
0
No-Load Supply Current vs V
Maximum V
Switch Current Limit
vs Duty Cycle
T
SYNC = LOW
A
= 25°C
5
0.1
20
10
0.2
LOAD CURRENT (A)
INPUT VOLTAGE (V)
DUTY CYCLE (%)
15
IN
MINIMUM
40
TYPICAL
T
T
0.3
for Full Frequency
A
A
= 25°C
= 85°C
20
0.4
60
25
0.5
30
V
L = 6.8μH
f = 2MHz
SYNC = 5V
T
O
80
A
= 5V
0.6
= 25°C
IN
35
3689 G04
3689 G10
3689 G07
100
0.7
40
800
700
600
500
400
300
200
100
0.5
35
30
25
20
15
2.0
1.5
1.0
10
0
5
0
0
–50
–50 –25
0
No-Load Supply Current
Maximum V
Switch Current Limit
vs Temperature
CATCH DIODE: DIODES INC. B140HB
V
V
IN
OUT
–25
= 12V
0.1
= 3.3V
0
0
0.2
TEMPERATURE (°C)
LOAD CURRENT (A)
TEMPERATURE (°C)
INCREASED SUPPLY
CURRENT DUE TO
CATCH DIODE LEAKAGE
AT HIGH TEMPERATURE
25
IN
25
SYNC = HIGH
SYNC = LOW
0.3
for Full Frequency
50
50
0.4
75
75
T
T
A
A
= 25°C
0.5
= 85°C
100
V
L = 4.7μH
f = 2MHz
SYNC = 3.3V
100
O
= 3.3V
0.6
125
125 150
3689 G05
3689 G11
3689 G08
150
0.7
600
400
300
200
1.2
1.0
0.8
0.6
500
100
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.4
0.2
LT3689/LT3689-5
0
0
0
0
6
4
Maximum Output Current, 3.3V
Maximum Load Current, 5V
Switch Voltage Drop
T
L = 12μH
f = 1MHz
A
= 25°C
8
200
T
12
T
A
A
12
= 125°C
SWITCH CURRENT (mA)
= 25°C
16
400
18
MINIMUM
MINIMUM
TYPICAL
TYPICAL
V
V
T
IN
IN
A
20
= –50°C
(V)
(V)
600
24
24
T
L = 12μH
f = 700kHz
28
A
800
30
= 25°C
OUT
32
3689 G12
3689 G06
3689 G09
OUT
3689fa
5
1000
36
36