Datasheet

10701fe
9
LT1070/LT1071
TYPICAL APPLICATIONS
U
(Note that maximum output currents are divided by 2 for the LT1071)
Positive Current Boosted Buck Converter
R3
680Ω
C1
0.33µF
200pF
*REQUIRED IF INPUT LEADS ≥ 2"
R4
1.24k
C2
5000µF
V
OUT
5V
10A
V
IN
28V
R1
5k
V
SW
•
•
V
IN
C3
0.47µF
C6
0.002µF
D2
470Ω
2W
1:N
N ≈ 0.25
LT1070
GND V
C
FB
1070/71 TA19
R6
470Ω
–
+
COMP
LM308
V
IN
R2
1k
R7
1.24k
R5
5k
V
–
7
D1
2
3
8
4
6
V
+
+
C5*
100µF
+
Positive to Negative Buck/Boost Converter
+
R1
11.3k
1070/71 TA05
V
OUT
12V
2A
V
IN
–12V
R3
2.2k
C1
0.22µF
R2
1.24k
*
**
REQUIRED IF INPUT LEADS ≥ 2"
PULSE ENGINEERING 92113
C2
1000µF
+
C4*
100µF
L1**
150µH
Q1
D1
V
SW
V
C
V
IN
LT1070
GND
FB
C3
L2
OPTIONAL
OUTPUT
FILTER
L3
OPTIONAL
INPUT
FILTER
+
R6
470Ω
1070/71 TA09
V
IN
10V TO 30V
*
**
REQUIRED IF INPUT LEADS ≥ 2"
PULSE ENGINEERING 92113
†
TO AVOID START-UP
PROBLEMS FOR INPUT
VOLTAGES BELOW 10V,
CONNECT ANODE OF D3
TO V
IN
AND REMOVE R5.
C1 MAY BE REDUCED FOR
LOWER OUTPUT CURRENTS.
C1 ≈ (500µF)(I
OUT
) FOR 5V
OUTPUTS, REDUCE R3 TO
1.5k, INCREASE C2 TO 0.3µF
AND REDUCE R6 TO 100Ω.
V
OUT
–12V
2A
R3
5k
R2
1.24k
C1
0.1µF
C5*
100µF
C3
2µF
+
C4
5µF
+
C1
†
1000µF
L1**
200µH
V
SW
V
C
V
IN
LT1070
R5
†
470Ω
1W
D3
†
1N4001
R1
10.7k
R4
47Ω
D2
1N914
D1
GND
FB
Negative to Positive Buck/Boost Converter