SU1690186A1 - Signal generator - Google Patents

Abstract

The invention relates to radio engineering and can be used in pulsed and analog equipment for various purposes, in particular in multichannel equipment for monitoring and measuring parameters AND digital circuits for generating reference signals with adjustable lengths of signal fronts. The purpose of the invention is to expand the scope by providing control of the steepness of the edges of the output signal. When the input signal is applied to the base of transistor 1, depending on the sign of the difference between the input and output signals, either the charge or discharge of the capacitor 7 is caused by the difference current of transistors 1, 2, which form a differential cascade. A decrease in voltage on the control bus leads to a decrease in the current of the controlled current source 5. This closes the transistors 8.9 and 3.4, converting the driver to a high impedance state. 1 il.

Description

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The invention relates to radio engineering and can be used in pulsed and analog equipment for various purposes, in particular in multichannel equipment for monitoring and measuring the parameters of digital circuits for generating reference signals with adjustable signal fronts.

The purpose of the invention is to expand the scope by providing control of the steepness of the edges of the output signal.

The drawing shows a schematic diagram of the shaper.

The signal conditioner contains transistors 1-3 of the same conductivity type, transistor 4 of the opposite conductivity type, controlled sources 5 and 6 of current, and capacitor 7. Controlled current source 6 is made of transistor 8 and 9.

The base of transistor 1 is connected to the input bus of the driver, the emitter is connected to the emitter of transistor 2, the base of transistor 4 and one output of a controlled current source 5, the other output of which is connected to the collector of transistor 4 and the first power bus, the input transistor is connected to the control bus, the transistor emitter 4 is connected to the emitter of the transistor 3, the base of the transistor 2 and the output terminal of the driver, the collector of transistor 2 is connected to the base of transistor 3, the collector of transistor 9 and through the capacitor 7 with a common bus, the collector of transistor 1 It is in common with the collector of transistor 8 and the bases of transistors 8 and 9, the emitters of which are connected to the collector of transistor 3 and the second power line.

The signal conditioner works as follows.

The on-state of the driver is determined by the presence of a control voltage on the control bus, setting the emitter current of the differential stage at transistors 1 and 2. The controlled current source 6 is made according to the current mirror circuit at the driving and reflecting transistors 8 and 9.

The controlled current source 6 sets the collector current of the reflecting transistor 9 to be equal to the current of the drive transistor 8, equal in turn to the current of the transistor 1 of the differential stage. Therefore, when the input signal is applied, the charge current of the capacitor 7 is equal to the difference of the currents of the first and second transistors 1 and 2. At the end of the input signal, the capacitor 7 is discharged by the difference current. Depending on the difference between the input and output

the voltage of the capacitor current 7 is either charging or discharging. Replacing capacitor 7 with a constant current causes a linear change in voltage.

on it, which is transmitted through the emitter follower on the transistor 3 to the output bus of the driver.

The control of the rate of change of the output signal is achieved in

the account of limiting the current of the recharge of capacitor 7 at the level of the difference of the currents of transistors 1 and 2.

When the control voltage decreases, the driver turns to

increased output impedance. In the absence of the emitter currents of transistors 1 and 2, the controlled current source 6 is closed and transistors 3 and 4 are de-energized.

Claims (1)

Invention Formula A signal conditioner containing the first, second and third transistors of the same conductivity type, the fourth transistor of the opposite conductivity type, the first controlled current source, whose input is connected to the control bus, the first output is connected to the emitters of the first and second transistors and the base of the fourth transistor, the second output is connected with the collector of the fourth transistor and the first power bus, the base of the first transistor is connected to the input bus forming device, the collector is connected to the input of the second controlled current source, the first output of which is connected to the collector of the second transistor and the base of the third transistor, the collector of which connected to the second output of the second controlled current source and the second power bus, the emitter is connected to the emitter of the fourth transistor, the base of the second transistor and the output bus of the driver, characterized in that in order to expand the field of application by providing control of the steepness of the output signal, into it a capacitor is introduced, the second controlled source current is made on the first and second transistors, the emitters of which are connected to the second power line, the bases are connected to the collector of the first transistor, the collectors of the first and second transistors of the second controlled current source are connected to the collectors of the first and second transistors, respectively, the capacitor leads are connected to the common busbar and base of the third transistor.