Ideal Op‐amp and Circuits
ƒOp‐amp Slew Rate
ƒOp‐amp Bandwidth
ƒBuild and characterize several circuits with AC signal inputs
INFORMATION
Texas Instruments
Op Amps For Everyone
http://www.ti.com/lit/an/slod006b/slod006b.pdf
Op‐amp Slew Rate
ƒSlew rate (SR) is the rate of change of the output voltage when a step input signal is applied at the input SR =
ΔV
Δt
ƒPrimary a function of internal compensation capacitor added to stabilize the op‐amps unity gain ƒNon‐compensated op‐amps exhibit larger bandwidths and larger slew rates, but stability of the circuit must be realized by other methods
ƒNote Settling Time determines when output is stable
Slew Rate
Settling Time
*Referenced :TI data sheets
Op‐amp Bandwidth
ƒUnity‐Gain Bandwidth ‐‐ usable frequency range ‐‐ flat response ‐‐ for gain = 1, function of op‐amp internals
ƒGain Bandwidth Product (GBP) ‐‐ is a constant for an amplifier
GBP = Gain × Bandwidth
or Bandwidth =
GBP
Gain
ƒUsable Bandwidth is also a function of Gain
*Referenced:
http://e2e.ti.com/support/amplifiers/precision_amplifiers/f/14/t/239054.aspx
Configuration 1 R2
R1
ƒBuild It with LM741 1. Verify reported slew rate
2. Determine bandwidth for small gain
3. Determine bandwidth for a gain of 100
ƒBuild It with NE5534 1. Verify reported slew rate
2. Determine bandwidth for small gain
3. Determine bandwidth for a gain of 100
LM741
Configuration 2 LM741
ƒBuild It with LM741 R1
1. Verify reported slew rate
2. Determine bandwidth for unity gain
3. Determine bandwidth for a gain of 100
ƒBuild It with NE5534 1. Verify reported slew rate
2. Determine bandwidth for unity gain
3. Determine bandwidth for a gain of 100
R2
Exercise: 1. Report slew rates and bandwidths.
2. Using the resources of your choice research and, in your own words, write a concise definition for:
a. Common mode voltage
b. Ground loop
Be sure to cite your references.