Operational Amplifiers, OP-AMPS
The Ideal OP-AMP
Ideal OP-AMP with Power Supplies
No terminal of the OP-AMP is physically connected to ground.
Functions and Characteristics of the Op-Amp
1. The Op-Amp senses the voltage difference at its
Bipolar Junction Transistors.
DEVICE STRUCTURE AND PHYSICAL OPERATION
Simplified Structure and Modes of Operation
The transistor consists of two pn junctions, the EBJ
and the CBJ
BJT Modes of Operation
SINGLE-STAGE MOS AMPLIFIERS
The Basic Structure
V DD = VSS = 10 V , I = 0.5 mA, RG = 4.7 M, R D = 15 15k, Vt = 1.5 v, and k n ' (W / L) = 1 mA / V 2
Find VOV , VGS , VG , VS , V D , g m and r0 assume V A = 75 V
BIASING IN MOS AMPLIFIER CIRCUITS
Biasing by Fixing VGS
The Bias point depends too much on the particular
Biasing by Fixing VG
Resistor RS introduces
feedback and changes VGS
if I D changes as when
transistors are interchanged.
VG = V
Analyze the circuit to determine
the voltage at all nodes and the
current trough al branches. Let
Vt = 1 V and
k n ' (W / L) = 1 mA / V 2 . Neglect the
channel length Modulation.
Design the circuit so that the transistors operate i
We will present the current voltage characteristic for DC to low frequency operation of the Enhancement type
Figure 4.10 (a) Circuit symbol for the n-channel
enhancement-type MOSFET. (b) Modified circ
MOS Field-Effect transistors (MOSFETs)
MOSFETS BJTs are three terminal devices, they are more useful than two terminal devices, and they could be used in:
Logic circuits and
The MOSFET has become the most widely used electronic dev
Physical Operation of Diodes
Band Theory of Solids
Some material from: http:/hyperphysics.phy-astr.gsu.edu/hbase/solids/intrin.html
Diffusion and Drift
J p = qD p
J n = qDn
J ( A / cm 2 )
n and p (atoms / cm 3)
Modeling The Diode Forward Characteristic
OPERATION IN THE REVERSE BREAKDOWN REGION ZENER DIODES Specifying and Modeling The Zener Diode
Use of the Zener Diode as a Shunt Regulator
v Z < 5 V TC < 0; TC (mV ) ; v Z > 7 V TC > 0; TC
MODELING THE DIODE FORWARD CHARACTERISTIC Graphical Analysis Using The Exponential Model
Iterative Analysis Using The Exponential Model
VDD = 5 V, R= 1 k ohm, ID= 1 mA @ 0.7 V VD hanges .1 V per every decade change in current
THE IDEAL DIODE
Current Voltage Characteristics
For circuit (a) find v 0 versus v .
The transfer characteristic.
For circuit a) sketch the waveform of v D .
v I peak is 10 V, R L = 1 k ohm , find i D pe
LARGE-SIGNAL OPERATION OF OP-AMPS
Output Voltage Saturation
Op-Amp with Rated Output Voltage of 13V
For Vp = 1 and RL = 1kohm, specify the signal resulting at the output of the amplifier.
For Vp = 1.5 and RL = 1kohm, specify the signal resulti
Also known as differential amplifiers. Ideally responds to the differential voltage and rejects the common mode
voltage. Practical circuits will have a combination of both modes.
v 0 = Ad v Id + Acm v Icm
The efficacy is usually meas
Bipolar Junction Transistors Characteristics.
Biasing Using a Collector to Base Feedback Resistor
VCC = I E RC + I B R B + V BE
R B + V BE
RC + R B /( + 1)
VCC = I E RC +
Conceptual circuit for measuring the iC VCB characteristic (comm