LT1072IT Datasheet, PDF (11/16 Pages) Linear Technology – Available in MiniDiP, TO-220, and TO-3 Packages

TYPICAL APPLICATIO S
D3^†
1N4001
C4 ⁺
5µF
Positive to Negative Buck-Boost Converter
R5^†
470Ω, 1W
V_IN
V_SW
LT1072
GND
V_C ^FB
R3
5k
C2
0.1µF
C5
100µF*
R1
10.7k
V_IN
10 TO 30V
D2 _R4
1N914 _47Ω
*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
+
R2
1.24k
C3
2µF
D1
L1**
200µH
+ _C1†
1000µF
R6
470Ω
V_OUT
–12V AT 2A
LT1072 • TA07
LT1072
External Current Limit
V_X
R2
R1
500Ω
≈ 2V
D1
LT1072
GND
V_C
LT1072 • TA08
Voltage Boosted Boost Converter
V_IN ⁺
15V
R4 C3
1.5k 0.68
1/2W
V_IN
V_SW
LT1072
GND
V_C ^FB
R3
10k
C2
0.047µF
D2
1 ^{TOTAL INDUCTANCE = 8mH}
L1 ^{INTERLEAVE PRIMARY AND}
N = 5 ^{SECONDARY FOR LOW LEAKAGE}
INDUCTANCE
R1
D1
98k
V_OUT
100V AT 75mA
R2
+
1.24k
C1
200µF
LT1072 • TA09
1072fc
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