Datasheet LT1070, LT1071 (Linear Technology) - 9

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