SU1698951A1 - Operational amplifier on cmis transistors - Google Patents

Abstract

The invention relates to amplifier technology. The purpose of the invention is to improve noise immunity by stabilizing the currents consumed from power sources. In an operational amplifier on a CMDR-resistor, an input differential stage 1 output stage 2 is used, performed on the first and second CMTP transistor 3, 4, additional transistor cascade 5, made on the third and fourth DTMP transistors 6, 7, and current reflector 8, made on the fifth and sixth CMOS transistors 9, 10. Additional cascade 5 and current reflector 8 at certain topological ratios of transistors on which they are performed. ensure the stability of gokhs consumed from the power source -i for any value of the input signal. ., running on both the power supply buses and the common bus, are constant and independent of the size of the input signal. As a result, the electromagnetic compatibility of the proposed device with other elements in the LSI connected to the same buses is increased. 1 il.

Description

The invention relates to amplifier technology and can be used in amplifiers for various purposes, especially those that are part of analog and analog-digital large integrated circuits on CMDP transistors.

The purpose of the invention is to improve noise immunity by stabilizing the currents consumed from power sources.

The drawing shows a circuit diagram of an operational amplifier on CMOS transistors.

The device contains an input differential stage 1, an input stage 2 at the first and second CMTP transistors 3 and 4, an additional cascade 5 at the third and fourth CMTP transistors 6 and 7 and a current reflector 8 at the fifth and sixth CMDP transistors 9 and 10.

Operational amplifier for CMOS transistors works as follows.

The input differential stage 1 amplifies the difference of the signals supplied between the inverting and non-inverting inputs. Output stage 2 provides additional signal amplification. Topologies about the third and fourth CMOS transistors 6 and 7 and CMD transistors reflect the current reflector so that at zero output voltage, when the current to the load connected between the output and the common bus is missing (), the current of the sixth transistor 1e is current of the first transistor h. The latter in this case is equal to the current of the second transistor M:

.(one)

When the input signal changes, the output voltage level changes and, consequently, the current in the load. Since the current M is constant, the changes in the currents 1И and З are always equal in magnitude and opposite in sign:.

Changes in the currents of the first and sixth transistors 3 and 10 are also opposite, obviously, in sign, since an increase in the current of the first transistor 3 leads to an increase in the current of the third transistor b, which, due to the constant current of the fourth transistor 7, causes a decrease in the current of the fifth transistor 9 and therefore, the current of the sixth transistor 10. The topology of transistors 6.7.9 and 10 can be chosen in such a way that the changes in the currents of the first and sixth transistors 3 and 10 will be equal in absolute value:

. (2)

Then the sum of the currents of the first and sixth transistors 3 and 10 is always constant and equal to 214. Therefore, when the level changes

the output voltage and the change in current in the load; the currents in the power rails and the common bus remain constant. This eliminates the possibility of the influence of the proposed device on the operation of other elements of the electronic device or LSI connected to the same power buses and the common bus, and thus increases the electromagnetic compatibility of the device with these elements. It can be shown that to satisfy condition (2), it is necessary to provide

one (av / hell) ayu, (3)

where ct denotes the ratio of Wi / Li width

channel of the 1st transistor x its length.

The ratio of the currents of the second and fourth transistors 4 and 7 must be selected as follows:

  SC / cti - "10/209. (4)

Satisfying the topological relations (3) and (4) ensuring the fulfillment of conditions (2) and (1) by setting the respective sizes of transistors 3, 4, 6, 7, 9 and 10 allows the device to fully stabilize the currents in the power supply and common bus.

An optocoupler on CMPE transistors with the same stability of current consumption and improved electromagnetic

compatibility can be realized by replacing p-channel transistors with p-channel and changing polarity of voltages on the power supply buses.

Claims (1)

Invention Formula An KMDP transistor operational amplifier containing an input differential stage and an output stage executed on the first and second CMTPtransistors, the first CMD transistor being connected according to the common source circuit, and the second CMTP transistor being connected according to the current generator circuit, characterized in that in order to improve noise immunity by stabilizing the currents consumed from power sources, an additional cascade is introduced into it, performed on the third and fourth CMTP transistors, the third CMCD transistor included in the circuit with a common source, and the fourth CMOS transistor is switched on according to the current generator circuit, and a current reflector, with the gates of the first and third, second and fourth CMTP transistors in pairs combined, the input of the current reflector is connected to the output of the additional stage, the output is connected to the common bus, and its common output to the sources of the first and third CMTP transistors.