LT1070 Datasheet, PDF (11/12 Pages) Linear Technology – 5A and 2.5A High Efficiency Switching Regulators

LT1070/LT1071
TYPICAL APPLICATIONS (Note that maximum output currents are divided by 2 for the LT1071)
Flyback Converter
V_IN
20V TO 30V
R4
+
C4*
100µF
V_IN
V_SW
LT1070
FB
GND V_C
R3
1.5k
C2
0.15µF
*REQUIRED IF INPUT LEADS ≥ 2"
L2
10µH
V_IN
OPTIONAL
C4
FILTER
200µF
0V
D1
C3
0.47µF
•
1
N
+
C1
V_OUT
5V
6A
0V
2000µF
D2
•
N = 1/3
R1
0
3.74k
0
R2
1.24k
0
V_SNUB
CLAMP TURN-ON
SPIKE
a
PRIMARY
FLYBACK
VOLTAGE
=
V_OUT +
N
V_F
b
V_OUT + V_F
LT1070/LT1071 SWITCH VOLTAGE
AREA “a” = AREA “b” TO MAINTAIN
ZERO DC VOLTS ACROSS PRIMARY
c
d
(N)(V_IN)
SECONDARY VOLTAGE
AREA “c” = AREA “d” TO MAINTAIN
ZERO DC VOLTS ACROSS SECONDARY
∆I
I_PRI
I_PRI N
I_PRI
PRIMARY CURRENT
SECONDARY CURRENT
LT1070 SWITCH CURRENT
I_PRI
t
=
(I_PRI)(L_L)
V_SNUB
SNUBBER DIODE CURRENT
1070/71 TA08
PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted.
K Package
4-Lead TO-3 Metal Can
(LTC DWG # 05-08-1311)
T Package
5-Lead Plastic TO-220 (Standard)
(LTC DWG # 05-08-1421)
0.320 – 0.350
(8.13 – 8.89)
0.420 – 0.480
(10.67 – 12.19)
0.760 – 0.775
(19.30 – 19.69)
0.060 – 0.135
(1.524 – 3.429)
0.038 – 0.043
(0.965 – 1.09)
1.177 – 1.197
(29.90 – 30.40)
0.470 TP
P.C.D.
0.655 – 0.675
(16.64 – 19.05)
0.151 – 0.161
(3.84 – 4.09)
DIA 2 PLC
72°
18°
0.167 – 0.177
(4.24 – 4.49)
R
0.495 – 0.525
(12.57 – 13.34)
R
K4(TO-3) 0695
0.390 – 0.415
(9.906 – 10.541)
0.460 – 0.500
(11.684 – 12.700)
0.057 – 0.077
(1.448 – 1.956)
0.147 – 0.155
(3.734 – 3.937)
DIA
0.165 – 0.180
(4.191 – 4.572)
0.230 – 0.270
(5.842 – 6.858)
0.570 – 0.620
(14.478 – 15.748)
0.620
(15.75)
0.330 – 0.370
(8.382 – 9.398)
TYP
0.700 – 0.728
(17.78 – 18.491)
0.152 – 0.202
0.260 – 0.320 (3.861 – 5.131)
(6.60 – 8.13)
0.028 – 0.038
(0.711 – 0.965)
0.135 – 0.165
(3.429 – 4.191)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
0.045 – 0.055
(1.143 – 1.397)
0.095 – 0.115
(2.413 – 2.921)
0.013 – 0.023
(0.330 – 0.584)
0.155 – 0.195
(3.937 – 4.953)
T5 (TO-220) 0398
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