Browse Prior Art Database

DC to DC Converter

IP.com Disclosure Number: IPCOM000091595D
Original Publication Date: 1968-Mar-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 33K

Publishing Venue

IBM

Related People

Briot, JC: AUTHOR

Abstract

The DC-to-DC converter comprises switching transistor T in series with magnetic core MC and load R1, the opposite end of which is grounded. The collector of T is connected to the DC input voltage +V. Capacitor C is connected in parallel with R1. Diode D is connected between the emitter of T and ground, in parallel with MC and R1. MC has a rectangular hysteresis loop b...e. A bias winding is fed with bias current Ip from a bias control circuit. N and Np are the numbers of turns of the main and bias windings respectively. T is alternately fully on or fully off under the control of pulses from pulse generator PG.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 78% of the total text.

Page 1 of 2

DC to DC Converter

The DC-to-DC converter comprises switching transistor T in series with magnetic core MC and load R1, the opposite end of which is grounded. The collector of T is connected to the DC input voltage +V. Capacitor C is connected in parallel with R1. Diode D is connected between the emitter of T and ground, in parallel with MC and R1. MC has a rectangular hysteresis loop b...e. A bias winding is fed with bias current Ip from a bias control circuit. N and Np are the numbers of turns of the main and bias windings respectively. T is alternately fully on or fully off under the control of pulses from pulse generator PG.

When T is on, D is reversely biased and the current goes from +V supply voltage to ground through T, MC, and load R1. When T turns off, the energy stored by MC is discharged in the circuit comprising MC, R1 and D.

In order to maintain the current relatively constant during the time T is fully on and constant also during the time T is fully off, it is necessary to prevent saturation of MC. The following two relationships are, therefore, necessary. The conducting state duration of T is less than or equal to the switching-up duration of MC. The blocking state duration of T is less than or equal to the switching-down duration of MC.

The pulse rate of generator PG is established so as to fulfill these requirements. Under these conditions, the current Ir through R1 is (Np Ip + Ic)/N when T is on and is (Np Ip - Ic)/N when T is off. Here Ic is t...