SU1208599A1 - Pulse-width modulator - Google Patents

Abstract

The invention relates to a pulse technique and can be used in secondary power sources. The device contains a generator 1 rectangular pulses, a transformer 2 with a winding 7 and a shunt 8, a source of 3 control voltages, a transistor switch 4 with current feedback, a load 5, a source 6 of the output voltage and a charging capacitor 9 of the source 3 of control voltage . The introduction of the winding 7 of the transformer 2 with the shunt 8 and the connection to the middle terminal of the primary winding of the source 3 of the control voltages has increased the sensitivity of the pulse width modulator and reduced the power of the control signal. 1 il. i (L

Description

The invention relates to a pulse technique and can be used in secondary power sources.

The purpose of the invention is to increase the sensitivity of a pulse width modulator S containing current feedback feedback transistors. The drawing shows a block diagram of a pulse width modulator,

The pulse width modulator contains a generator of 1 rectangular pulses, a transformer 2, a source of control voltages 3, a transistor switch 4 with current feedback, a load of 5, a source of 6 output voltages, and a shunt 7j winding 8 and charging KOH; j, e icaTop 9 of the source of control voltages 3, while the generator 1 of rectangular pulses is connected to the primary winding of the traps (|) 0 of the armature 2, to the middle output of which are connected zheny and zar dnsh capacitor 9 transistor switch 4 with current reverse with The transducer contains a transistor, the first secondary winding of the transformer 2 is connected to the base and to the emitter, and the second secondary winding of the transformer 2 is connected to the emitter and one of the terminals of the output voltage source 6. and another pin of source 6 of the output voltage. A transformer is wound on the transformer 2 on a winding 7, to the terminals of which shunt 8 is connected, Shunt 8 can be

made low resistor- ;; or

inductive.

Pulse-width modulator works as follows.

From the generator 1 of rectangular pulses to the control winding — the primary winding of the transformer 2 — impulses a pulse, which opens the transistor key 4. As a result of the presence of positive current feedback, the key is opened quickly. The selection of the turns of the additional winding 7 and the inductance of the shunt 8 transformer 2 is applied to the nonlinear part of the curve of the magnetization of the ferromagnetic material. Magnetic permeability I jf vl 2SSSi 2uiil 2 L .. "... B.

What is the inductive, theft 818 Subscription

GUL Patent branch, Uzhgorod, ul. Project A

992

The function of induction B and Voltage n decreases with increasing voltage at the output of source 3 of control voltages (i.e. with increasing current through the control winding of transformer 2). Current feedback transistor switch 4 in this mode is essentially blocking-g

nerator with a constant time t- Due to the non-linearity of the dependence of jU on voltage, the inductance L 3 and therefore 5 and the duration of the current pulse flowing in the load 5 changes. By changing the voltage at the output of the source 3 control voltages, 5 widely ..

The introduction of an additional winding of a transformer with a shunt and connection to the middle output of the primary winding of the source of control ap- plications allows to increase the sensitivity of the pulse-width modulator and reduce the power of the control signal.

Formula

gaining

Claims (1)

1. Pulse width modulator, containing a source of control ria- and W, a square pulse generator, the outputs of which are connected to the terminals of the primary winding of a transformer, the first secondary winding of which is connected to the base and emitter of the transistor switch, and the second secondary winding is connected to the emitter and the first output of the output voltage source, the melody whose second output and the collector of the transistor switch include the load, tl and g and y u u and s topics what. ... B. d) a target of sensitivity increase, a winding was inserted into it on a t-shaped-form. additional winding,: .-. The terminal of which is connected to the shun-t and the source of the control voltage is connected to the middle terminal of the first winding of the transformer, 2, the modulator according to claim; .. about t and h . the fact that in it the gezt zzapolnen - from the coarse resistance. 3. The modulator of clause 15 of the clause and the fact that in it the shun is made inductive, theft 818 Subscription