SU826307A1 - Current stabilizer - Google Patents

Description

I

The invention relates to electrical engineering and can be used to power an electronic device.

- Knob stabilizers are known, containing regulating and amplifying transistors of the same type of conductivity, current sensor - diode, bias resistor, the regulating transistor being connected to the collector with a terminal for connecting the load, directly with the collector of the amplifying transistor and connecting the power source through the resistor bias, and the emitter - with the base of the amplifying transistor, which through the current sensor is connected to the emitter and obdasm output to L2J.

A disadvantage of the known stabilizers is the low stability of the output current when the voltage of the power supply varies.

The purpose of the invention is to increase the stability of the output current when the voltage of the power source is changed.

This goal is achieved by additionally introducing a chain of series-connected resistors and a reference voltage source, connected between the base of the amplifying transistor and the output for connecting the power source.

In this case, in order to extend the range of adjustment of the output current, the current sensor consists of two parallel-connected diodes.

The drawing shows a circuit diagram of the device.

The current stabilizer contains a regulating transistor 1, the base and emitter of which are connected respectively to the collector and the base of the amplifying transistor 2. Between the base of the transistor 1 and the output 3 of the stabilizer, a resistor 4 is connected, the load of the transistor 2. the transistor 2 and the terminal 3 switched on the compensating circuit from the series-connected resistor 7 and the source 8 of the reference voltage. The output of the stabilizer is zero output 9. The two-port 10 is the stabilizer load. Consider the static mode of operation of a stabilizer, in which its output current is increased in stability against changes in the voltage of the source with a supply voltage E ,. The constant currents flowing through resistors 4 and 7 are respectively t 34 ::::. E. -We5a: Wop8

V

where is vgg and

voltage between

e6, base and emitter of transistors 1 and 2

V. voltage on the CTCT bilitron 8;

 Ry resistance of resistors 4 and 7. Considering that parallel to the emitter-base junction of transistor 2 are two diodes with the same volt-ampere characteristics (VAC) as the BAX of the emitter-base junction of transistor II, you can find the emitter and collector currents but,. (2)

Based on relations (1) and

get 2

,

If the resistance of the resistor 4 is chosen twice as large as the resistance of the resistor 7 () then the expression (3) results in

, .B-, c4,

7 RT

Claims (2)

1. A current stabilizer containing regulators and amplifying transistors of the same type of conductivity, a current sensor — a diode, a bias resistor, the regulating transistor being connected to the collector with a collector for connecting the load, and with the collector of the amplifying transistor directly with the collector through the bias resistor, and the emitter - with the base of the amplifying transistor, which is connected through the current sensor with an emitter and a common terminal, characterized in that, in order to increase the stability of the output current when the voltage of the power source is changed, a chain of series-connected resistors and a voltage source is included in the stabilizer, connected between the base of the amplifying transistor and the output for connecting the power source . 2. Stabilizer according to claim 1, characterized in that the dat74 Thus, with R, the elecator current of the transistor 1 does not depend on the supply voltage (4). Consequently, a change in the voltage of the power source E does not affect you & the current of the stabilizer. In shuttering with known current stabilizers, the proposed device has the best (5–20 times) stability of the output current. The application of the proposed device in operational amplifiers, generators of linearly varying voltage, if. allows the development of circuits operating in a wide range of supply voltages. Not only zener diodes, but also shifted semiconductor diodes, transistors in the mode of reversible breakdown of pn junctions, transistor equivalents of zener diodes, etc. can be used as a source of the reference voltage. Instead of a bipolar transistor 1, it is possible in some cases to incorporate field effect transistors or Darlington cascades into the current regulator circuit (component active elements) Chik current consists of two parallel-connected diodes. Sources of information taken into account in the examination 1. US Patent 3588672, cl. 323-4, 197. 2. Japanese patent number 49-9819, class, 58 N 2, 1974. 3 -o + f / s V 7s