Opamp Circuits

Inverting Opamp

with schemdraw.Drawing() as d:
    op = elm.Opamp(leads=True)
    elm.Line().down(d.unit/4).at(op.in2)
    elm.Ground(lead=False)
    Rin = elm.Resistor().at(op.in1).left().idot().label('$R_{in}$', loc='bot').label('$v_{in}$', loc='left')
    elm.Line().up(d.unit/2).at(op.in1)
    elm.Resistor().tox(op.out).label('$R_f$')
    elm.Line().toy(op.out).dot()
    elm.Line().right(d.unit/4).at(op.out).label('$v_{o}$', loc='right')

Non-inverting Opamp

with schemdraw.Drawing() as d:
    op = elm.Opamp(leads=True)
    out = elm.Line().at(op.out).length(.75)
    elm.Line().up().at(op.in1).length(1.5).dot()
    d.push()
    elm.Resistor().left().label('$R_1$')
    elm.Ground()
    d.pop()
    elm.Resistor().tox(op.out).label('$R_f$')
    elm.Line().toy(op.out).dot()
    elm.Resistor().left().at(op.in2).idot().label('$R_2$')
    elm.SourceV().down().reverse().label('$v_{in}$')
    elm.Line().right().dot()
    elm.Resistor().up().label('$R_3$').hold()
    elm.Line().tox(out.end)
    elm.Gap().toy(op.out).label(['–','$v_o$','+'])

Multi-stage amplifier

with schemdraw.Drawing() as d:
    elm.Ground(lead=False)
    elm.SourceV().label('500mV')
    elm.Resistor().right().label(r'20k$\Omega$').dot()
    O1 = elm.Opamp(leads=True).anchor('in1')
    elm.Ground().at(O1.in2)
    elm.Line().up(2).at(O1.in1)
    elm.Resistor().tox(O1.out).label(r'100k$\Omega$')
    elm.Line().toy(O1.out).dot()
    elm.Line().right(5).at(O1.out)
    O2 = elm.Opamp(leads=True).anchor('in2')
    elm.Resistor().left().at(O2.in1).idot().label(r'30k$\Omega$')
    elm.Ground()
    elm.Line().up(1.5).at(O2.in1)
    elm.Resistor().tox(O2.out).label(r'90k$\Omega$')
    elm.Line().toy(O2.out).dot()
    elm.Line().right(1).at(O2.out).label('$v_{out}$', loc='rgt')

Opamp pin labeling

This example shows how to label pin numbers on a 741 opamp, and connect to the offset anchors. Pin labels are somewhat manually placed; without the ofst and align keywords they will be drawn directly over the anchor position.

with schemdraw.Drawing() as d:
    d.config(fontsize=12)
    op = (elm.Opamp().label('741', loc='center', ofst=0)
                 .label('1', 'n1', fontsize=9, ofst=(-.1, -.25), halign='right', valign='top')
                 .label('5', 'n1a', fontsize=9, ofst=(-.1, -.25), halign='right', valign='top')
                 .label('4', 'vs', fontsize=9, ofst=(-.1, -.2), halign='right', valign='top')
                 .label('7', 'vd', fontsize=9, ofst=(-.1, .2), halign='right', valign='bottom')
                 .label('2', 'in1', fontsize=9, ofst=(-.1, .1), halign='right', valign='bottom')
                 .label('3', 'in2', fontsize=9, ofst=(-.1, .1), halign='right', valign='bottom')
                 .label('6', 'out', fontsize=9, ofst=(-.1, .1), halign='left', valign='bottom'))
    elm.Line().left(.5).at(op.in1)
    elm.Line().down(d.unit/2)
    elm.Ground(lead=False)
    elm.Line().left(.5).at(op.in2)
    elm.Line().right(.5).at(op.out).label('$V_o$', 'right')
    elm.Line().up(1).at(op.vd).label('$+V_s$', 'right')
    trim = elm.Potentiometer().down().at(op.n1).flip().scale(0.7)
    elm.Line().tox(op.n1a)
    elm.Line().up().to(op.n1a)
    elm.Line().at(trim.tap).tox(op.vs).dot()
    d.push()
    elm.Line().down(d.unit/3)
    elm.Ground()
    d.pop()
    elm.Line().toy(op.vs)

Triaxial Cable Driver

with schemdraw.Drawing() as d:
    d.config(fontsize=10)
    elm.Line().length(d.unit/5).label('V', 'left')
    smu = (elm.Opamp(sign=False).anchor('in2')
                      .label('SMU', 'center', ofst=[-.4, 0], halign='center', valign='center'))
    elm.Line().at(smu.out).length(.3)
    d.push()
    elm.Line().length(d.unit/4)
    triax = elm.Triax(length=5, shieldofststart=.75)
    d.pop()
    elm.Resistor().up().scale(0.6).idot()
    elm.Line().left().dot()
    elm.Wire('|-').to(smu.in1).hold()
    elm.Wire('|-').delta(d.unit/5, d.unit/5)
    buf = (elm.Opamp(sign=False).anchor('in2').scale(0.6)
                         .label('BUF', 'center', ofst=(-.4, 0), halign='center', valign='center'))

    elm.Line().left(d.unit/5).at(buf.in1)
    elm.Wire('n').to(buf.out, dx=.5).dot()
    elm.Wire('-|').at(buf.out).to(triax.guardstart_top)
    elm.GroundChassis().at(triax.shieldcenter)