Switch-mode power supply

EE 98 July/August 1986 179 One of the major problems in the design of switch mode power sup- plies is that most available (and suitable) ICs only offer the absolutely necessary facilities and not, for in- stance, thermal or short-circuit pro- tection. Linear Technology offers a solution to these problems with their LT1070 range of switching ICs. These devices are as easy to use as the familiar 3-pin regulator ICs. All steps have been taken to make the design of a simple, yet efficient, switch mode supply as easy as possible. The peak output current is 5 to 9 A, and a current-limiting circuit is provided. The diagram shows a switch mode DC-to-DC converter, whose output voltage may lie between 12 and 48 V, provided the input voltage is greater than 3 V. The input voltage of the cir- cuit as shown must always be lower than the output voltage. It is, how- ever, possible to modify the circuit to obtain an output voltage that is lower than the input voltage. One of the modifications is ...