RU2524853C2 - Mis transistor-based power switch - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to pulse engineering and can be used in different switching devices. The MIS transistor-based power switch comprises a transformer, a resistor, a diode and two p-n-p- and n-p-n-type transistors; the emitter of the p-n-p transistor is connected to the beginning the secondary coil of the transformer, the end of which is connected to the source of the MIS transistor, and through the resistor to the base of the p-n-p transistor, the collector of which is connected through the diode in reverse bias to the gate of the MIS transistor; the transformer includes an additional secondary coil, the beginning of which is connected to the end of the secondary coil of the transformer and the end of the additional secondary coil is connected through an additional resistor to the base of the n-p-n transistor, the collector-emitter junction of which is connected in parallel to the gate-source leads of the MIS transistor.

EFFECT: high reliability.

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Description

The invention relates to a pulse technique and can be used in various switching devices.

There is a known power switch on an MOS transistor containing an isolation transformer, a diode and two resistors (micro-assemblies VKU8-3.01 KSNL.4010104.001-01 TU, the parameters of which are shown on sheet 4, and the block diagram on sheet 51). This key has galvanic isolation from the control circuits and unipolar control of the MIS transistor, which provides this key with resistance to breakdown of the gate dielectric along the track of a nuclear particle (Ivanov N.A., Mitin E.V., Pashuk V.V., Tverskoy M. G. SEGR - effect in proton-irradiated MOS transistors. Radiation resistance of electronic systems, “Stability - 2010", scientific and technical collection, issue 13, M., 2010, pp. 95-96).

The disadvantage of this key is the long shutdown time, because The gate-source capacitance discharge of the MOS transistor occurs through a high-resistance discharge resistor.

The closest to the proposed technical essence is the power switch on the MOS transistor, containing a transformer, a resistor, diodes and two transistors, emitters and bases of two complementary transistors are connected directly, the emitters of the transistors are connected to the beginning of the secondary winding of the transformer, the end of which is connected to the source of the MOS- transistor and through a resistor to the bases of transistors, the collectors of which are connected through the diodes in the unlocking direction to the gate of the MOS transistor (patent RU No. 2337473), which is selected as prototype.

The disadvantage of the prototype is the bipolar control of the MOS transistor, which reduces its resistance to the effect of SEGR and leads to a decrease in reliability.

The aim of the invention is to increase reliability.

This goal is achieved by the fact that in the power switch on the MOS transistor containing a transformer, a resistor, a diode and two pn-p- and npn-type transistors, the emitter of the pn-p transistor is connected to the beginning of the transformer secondary winding, the end of which is connected to the MIS source -transistor and through a resistor - with the base of the transistor pn-p, the collector of which through the diode in the unlocking direction is connected to the gate of the MOS transistor, an additional secondary winding is introduced into the transformer, the beginning of which is connected to the end of the secondary winding of the transformer, and A second secondary winding through an additionally introduced resistor is connected to the base of the n-p-n-transistor, the collector-emitter junction of which is connected in parallel with the gate-source terminals of the MOS transistor.

The drawing shows a circuit diagram of a power switch on an MOS transistor (to simplify the drawing, it does not show the base-emitter resistors of transistors 4 and 5).

The power switch on the MOS transistor contains: a transformer (1) with a primary winding (2) and a secondary winding (3); two transistors (4) and (5) p-n-p- and n-p-n-type; the emitter of the transistor (4) is connected to the beginning of the winding (3), and the collector through the diode (6) in the unlocking direction with the gate of the MOS transistor (7); the end of the winding (3) is connected directly to the source of the MOS transistor (7) and through the resistor (8) to the base of the transistor (4); the beginning of the additional secondary winding (9) is connected to the end of the winding (3); the end of the winding (9) through an additional resistor (10) is connected to the base of the transistor (5), the collector-emitter junction of which is connected in parallel with the gate-source terminals of the MOS transistor (7).

The device operates as follows.

When applying to the input of the device on the primary winding (2) of the transformer (1) short positive pulses with high duty cycle, the secondary positive windings (3) also have short positive pulses with high duty cycle.

The positive potential from the beginning of the secondary winding (3) goes to the emitter of the transistor (4), and the negative potential from the end of the secondary winding (3) goes to the source of the MOS transistor (7) and through the resistor (8) to the base of the transistor (4) of type pn -r and it opens, and the positive potential from the beginning of the secondary winding (3) through the open transistor (4) and the diode (6) enters the gate of the MOS transistor (7), the negative potential from the end of the secondary winding (3) directly goes to the source MOS transistor (7), there is a fast charge of the gate-source capacitance of the MIS-t anzistora (7), and it opens.

In the pause between short positive pulses on the secondary winding (3) at the end of the additional secondary winding (9) there is a small positive voltage, but its value is not enough to open the transistor (5) through the emitter of the transistor (5), winding (9), resistor ( 10), the base of the transistor (5), and it will be closed. The gate-source capacitance of the MOS transistor (7) remains charged with a positive voltage, and therefore it remains open.

When short negative pulses are applied to the input of the device to the primary winding (2) of the transformer (1), positive pulses appear at the end of the additional secondary winding (9), which through the resistor (10) will open the transistor (5), and it will discharge the gate-source capacitance MOS transistor (7) to a voltage close to zero, and the MIS transistor (7) closes.

In the proposed device, the prototype performance is preserved due to active shunting of the gate-source capacitance of the MOS transistor (7) by the transistor (5) and the negative gate voltage is eliminated and, therefore, reliability is increased when exposed to heavy charged particles.

A prototype device was assembled on a TIL2 V transformer, resistors R (8) = R (10) = 470 Ohm and RB-e (4) = RB-e (5) = 240 Ohm, MOS transistor (7) 2P794A4, diode (6) 2D510A and transistors 2T313A, 2T3117A.

When controlling pulses with an amplitude of 7 V for a duration of 10 μs and a period of 112 μs, the on-time was 0.5 μs, the off time was 0.1 μs, with U max = 6.5 V, U min min = 0.012 V.

Of the patent information materials known to the applicant, no signs were found that are similar to the totality of the features of the claimed object.

Claims (1)

A power switch on an MOS transistor containing a transformer, a resistor, a diode and two pn-p and n-p-n-type transistors, the emitter of the pn-p transistor is connected to the beginning of the secondary winding of the transformer, the end of which is connected to the source of the MOS transistor, and through the resistor - with the base of the transistor pnp, the collector of which through the diode in the unlocking direction is connected to the gate of the MOS transistor, characterized in that an additional secondary winding is introduced into the transformer, the beginning of which is connected to the end of the transformer secondary winding, and the end is additionally through the secondary winding additionally introduced resistor connected to the base n-p-n- transistor, the collector - emitter of which is connected parallel to the gate terminal - MISFET source.