BWD MINI-LAB 603B User manual

MINI-LAB
BWD Precision Instruments Pty. Ltd.
(Incorporated in Victoria)
P.O. Box 298, Mulgrave North. 3170
5Dunlop Road, Mulgrave Vic. 3170 Australia
Phone [phone]
Telex AA 35115
Issue 23.

BWD 603B
MINI-LAB
TABLE OF CONTENTS
SECTION DESCRIPTION
GENERAL
PERFORMANCE
CONTROLS AND THEIR FUNCTIONS
OPERATION
APPLICATIONS
CIRCUIT DESCRIPTION
ALIGNMENT
MAINTENANCE
REPLACEMENT PARTS
GUARANTEE
PARTS LIST
L
1
2
3
4
5
6
7
8
9
10
11

INSTRUMENT HANDBOOK
MODEL BWD 603B MINI-LAB
1. GENERAL;
The MINI-LAB provides seven independent instruments in asingle compact
cabinet for use in the laboratory or classroom to supply signals and power
for awide range of measurements and experiments in the fields of electronics,
chemistry and bio-medical engineering.
The functions available include;-
(a) Sine, square, triangle, pulse and ramp generator with variable symmetry
and D.C. offset controls producing awide variety of waveforms from
0.001 Hz to IMHz which can be amplitude and frequency modulated by
an external signal
.
(b) Aramp generator 5sec to 50m sec.
(c) Aswitched power amplifier/bi-polar power supply/5 Volt supply combination.
(d) An operational Amplifier with variable gain.
(e) Two variable power supplies -1 to -15V and +1 to +15V at 1Ampere output.
(f) A0»-+ 200V variable power supply.
Acentre tapped 12.6V A.C. supply, and
(h) Numerous instrument combinations by link interconnection.
603B 1-IE

2.PERFORMANCE :
Funcfion Generafor :
2.1 Waveform: Sine, triangle or square, pulse and ramp with amplitude or
frequency modulation.
2.2 Frequency range: 8Decade ranges calibrated from 0.01 Hz to 1MHz plus a
200kHz to 2MHz range. An additional uncalibrated section of the dial
extends range to 0.001 Hz. Dial covers 2decades on each range.
Calibration: ±3% of full scale lOHz -IMHz.
2.3 Voltage output: Two simultaneous levels 10 Volts p-p open circuit, 5Volts p-p
into 600Q.
1Volt p-p open circuit, 0.5 Volts p-p
into 600Q.
Variable output provides continuous control of >100:1 of both outputs whilst
maintaining aconstant 600Q output impedance. Outputs, overvoltage and
short circuit proof.
Sinewave output level :Less than ±2% level variation over calibrated frequency
range into 600Q ±5%between 1and 2MHz.
2.4 Output offset: Output normally centered symmetrically about ground. Push/pull
switch applies acontinuously variable 0to ±5 Volts offset voltage on open
circuit. Control also doubles as ramp frequency control (see 2.8 below).
NOTE: 0-1 Voutput has ±0.5V offset.
2.5 Syr.in'.otry (fixed): ±2% from O.OlHz to 1MHz (calibrated portion of dial).
Symmetry (variable) :Pulse or ramp waveforms. Continuously variable from
1:1 to over 1:50 or 50:1 by switch selection. Applies to sine, triangle or
square waveforms. Variable control also doubles as ramp amplitude (see 2.8 below).
2.6 Sine wave distortion: <1.5% lOHz to >50kHz <2% at IMHz (typically
0.6% 20Hz to 50kHz).
Square wave rise time: lOOnsec into 600Q load and <50pf capacitance.
Triangle linearity: >99% within calibrated range on dial up to lOOkHz.
Triangle symmetry: Better than 2% within calibrated range up to lOOkHz.
2.7 Frequency modulation: Function Generator can be swept over 2decades by the
internal ramp generator or over 4decades by an external log sweep. It can
also be used as an externally programmed oscillator over a10,000/1 frequency
range.
Input: 1Volt/dial division.
Input impedance: 25KQ.
Linearity: 2%.
Input frequency: DC to >10kHz.
2.8 Sweep ramp generator:
Output voltage: 0to >+10 Volts with acontinuously adjustable upper limit
from +0.6 to +10 Volts using the variable symmetry control in the OFF mode.
Ramp duration :>4 sec to 65m sec approximately.
Continuously adjustable by the OFFSET control in the OFF position.
When coupled into the FM socket, the Function Generator will sweep from the
frequency selected by the dial up to the frequency set by the ramp amplitude
control. An automatic circuit prevents the sweep exceeding the dial range.
Horizontal drive to oscilloscope or recorder is also taken from ramp output
via the voltage amplifier (see 2.14) to set drive voltage and polarity required.
2-1
603b

2. PERFORMANCE (continued)
2.9 Amplitude Modulation: 0to 100% modulation all output waveforms from O.OOlHz
to 2MHz.
Input; 4volts p-p for 90% modulation.
'
Input resistance: approximately lOKQ.
Modulation input range: DC to 250kHz. An input voltage may also be used to
control the output level remotely from 0.5 to 20 volts p-p. NOTE: Unmodulated
carrier output level is 10 volts p-p, and 20 volts p-p at peak modulation
(open circuit). Both AM and FM modulation can be applied simultaneously.
2.10 TTL Output: Identical pulse width to main output. >3volts output into
2TTL inputs. <80n sec rise and fall time.
Selectable Power Source:
2.11 Amplifier
Gain: Voltage, fixed xlO. Input 3volts p-p for 30 volts p-p output maximum.
Current gain approximately x5000.
Input: lOKQ, inverting input only.
Frequency response: DC to >80khz at 20 volts p-p into 15Q.
Rise time: <5p sec for ±10 volts output swing.
Maximum output: ±15 volts minimum ±1 amp current (automatic
overload). 7Watts RMS into 15Q load. ±15 volts into>15Q.
Distortion: <0.1% at 1kHz increasing to <0.5% at 20kHz at full output
(+ 15 volts into 15Q).
Hum and noise; 60db below max. output (<30mV p“p).
Output impedance; <0.2Q.
2.12 Bi-Polar power supply
Voltage Range: Continuously variable from +15 volts through zero to -15 volts.
Current 1amp maximum at any voltage setting (automatic overload).
Output impedance: <0.2Q.
Hum and noise: <25mV p-p (5mV rms) at full output (15 volts at 1amp).
2.13 Fixed power supply:
Voltage +5volts
Current 1amp with automatic overload
Output impedance: <0.5Q.
Hum and noise: <25mV p-p at full output (8mV rms).
Voltage/Operational amplifier;
2.14 Amplifier
Gain: Continuously variable from xl to xlOO approximately.
Input: Balanced lOKQ each side to ground with gain control in circuit.
Input overvoltage proof.
Frequency response; DC to >80kHz -3db at all gain settings.
Slew rate; 4V/p sec.
Output lmpedance:<500fi (short circuit proof).
Output noise at XICO gain (input open circuit): <40mV p“p.
2-2 603B

2.PERFORMANCE (continued)
2.15
Operational amplifier
Input 0.5M^ isolated by switch
Performance characteristics see fig. 2a and b.
Large Signal Frequency
Response
I
•iSM 1M 2M 5M IDM 20M SOM
FR£QUeNCY(Ht)
Open Loop Frequency
Response
“1
s——
1
T*»2S C
V
NV,*
_| 1
“1 kPHASi Z
nKi—
'
r
CAJN\\
.20 1I I -IIIt
to 100 UtOk t00t> 1M 10M IQOM
FREQUENCY (Hii
Fig. 2a Fig. 2b
Low Voltage Power Supplies :
2.16 Voltage output: Two independent variable outputs v/ith acommon but
isolated zero line (200 volts DC isolation).
Range +1^ to +15 volts and -• 1^ to -15 volts or asingle ±3 to 30 Volts.
Current output: 1amp maximum each output -overload protected.
Regulation: for 10% line change, or 0to 1amp load change.
(Typically >0.5%).
Hum and noise: >5mVRMS at full load.
NOTE: Minimum voltage approximately IV to 2V.
High Voltage Power Supply :
2.17 Specifications apply at anominal input voltage of 235/117 volts AC.
Voltage output 0to 200 volts DC. 30m amp available at 175 volts DC.
20m amps at 200 volts EX^. Constant current overload at approximately
40m amp.
Output referred to ground.
Regulation: 1% for 10% line change from nominal input voltage, or 0
to 30m amp load change measured at 150 volt output.
Hum and noise: >25mV RMS at full output.
AC Supply ;
2.18 Voltage and current 6.3 volts to 0to 6.3 volts 1amp each side..
Completely isolated and each 6.3 volt leg is separately fused.
f'ucilities by Interconnection:
2.19 Power Waveform Output (2.1 with 2.11)
Function generator linked to power amplifier
Frequency range: 0.001 Hz to >80kHz.
Output: 0-30 volt p-p with 1amp capability. Output may be
symmetrical or offset about ground to ±15 volt p-p (minimum).
2.20 A.M. Modulation At Line Frequency. (2.9 with 2.18).
With 6.3 Volt AC supply linked to A.M. input via a39KSi resistor, sine
output will be 90% approximately A.M. modulated. Carrier output
range 0.001 Hz to 2MHz.
603B 2-3

2. PERFORMANCE (continued)
2.21 F.M. Modulation at Line Frequency (2.7 with 2.18)
Linked as for A.M. but to F.M. socket with a39KQ resistor, sine, square
or triangle will be swept over- adecade range of calibrated dial frequency.
2.22 Swept Output (2.7 with 2.8)
The function generator output may be swept over the entire 2decade range
of the dial on any range or down to <10% of any portion of the dial.
2.23 High Sensitivity Power Amplifier (2.11 with 2.14)
With operational amplifier linked to power amplifier.
Output; As for power amplifier specification.
Voltage gain; Continuously variable from xlO to xlOOO.
Frequency response; DC to >20kHz.
2.24 Function Generator Op Amp Link (2.1 with 2.14)
Push-pull signals; With generator output linked to inverting input asignal
180° out of phase with the generator is obtained at frequencies up to 80kHz.
±Pulse output; Sharp pulses to >100kHz can be generated by over-
driving the op-amp with offset triangular waveforms. Rise time is controlled
by degree of overdrive and op-amp gain. Other waveforms such as half
sine, log curves, truncated triangular and complex shapes of almost infinite
variety can be obtained by combining the wide range of facilities provided.
2.25 Power Supply; +45 volt 1amp (2.12 with 2.16)
By linking the -15 volt output to the bipolar output, output voltages to +45
volts can be set. By connecting the +15 volt output to the bi-polar supply
voltages to -45 volts can be set.
2.26 Modulated Power Supply. ±45 volt 1amp (2.1 and 2.11 with 2.16)
If the bipolar supply is switched to power amplifier and its input linked
to the function generator the low voltage supply can rise on top of the
amplifier output at low frequencies to provide for example, simulated power
line ripple.
2.27 Other facilities.
The generation of complex waveforms and many, experiments and measurements
are described in the applications section (Section 5) of this manual.
General Details;
2.28 Power requirements;
l90^°o^265'^vo?ts )
-60Hz, By switch selection (rear panel).
2.29 Finish; Light coloured panels and sage green vinyl coated aluminium covers
with anodised aluminium surrounds.
2.30 Warranty; The instrument is guaranteed for aperiod of twelve (12) months
against faulty materials and workmanship.
2.31 Dimensions; 420mm (I62") wide x200mm (8") high x260mm (10-1/4") deep.
Overall knobs, etc.
2-4 603B

2. PERFORMANCE (continued)
General Details (Cont'd)
2.32 Weight: 10kg (21 lbs) net, 11kg (24 lbs) packed.
2.33 Safety Standards: This instrument is designed to closely conform to lEC 348
recommendations.
2.34 Ordering Code: BWD 603B.
Accessories:
Dust Cover Part No. D28.
For full range of accessories suitable for educational experiments, see
separate list of 600 accessories.
2.35 Additional Products:
Oscilloscopes: Awide range of instruments are manufactured by BWD
Instruments from single channel 6MHz to dual trace lOOMHz oscilloscopes
including storage oscilloscopes to display, measure or store your 'MINI-LAB' .
waveforms.
600 SERIES ACCESSORIES:
600B Electromagnet with 1metre leads and 19mm square 75mm long pole
piece.
600C 24V lamp mounted with leads and plugs.
600D Microphone with 1metre screened lead and input plugs.
600E Interconnecting leads, 1metre long, fitted with 4mm stacking plugs.
600F 7Pin valve base on stand. Complete with 6AU6 valve.
600G Transistor mounted on stand. Complete with 2N3054 silicon NPN
power transistor.
600H 4Silicon diodes (2 amp). Diodes type BYX21-200.
6001 400kHz -2mHz parallel resonant circuit and detector diode.
600L R.C. charging circuit. Time constant 1sec.
600M L.C. charging circuit. Time constant 1sec.
600N 30Q 100mm loudspeaker on stand.
603B2-5

PERFORMANCE (continued)
600 Series Accessories (continued)
600P C.L. &Rphase and impedance circuit.
600Q Low voltage relay with change over contacts.
These are but asample of the wide range of accessories available for educational
fields in electronics and electrical engineering from BWD PRECISION INSTRUMENTS
PTY. LTD.

3. CONTROLS AND THEIR FUNCTIONS;
The front panel is divided into three major sections:-
3.1 Signal Source, comprising of afunction generator, pulse output,
amplitude modulator and aramp generator.
3.2 Amplifier section, containing aswitchdble Power Amplifier/Bi Polar Power
Supply, and aswitchable Voltage/Operational Amplifier.
3.3 Power Supply section, containing three independently variable power supplies
and one AC source at line frequency.
6719 21 20 31 30 28 29
13 10 8912 14 11 17 15 18 16 22 23 26 24 25
Signal Source Controls.
1.Frequency Range Switch: Desired frequency range can be obtained by
depressing the correct button. When the xO.l
and xl buttons are depressed simultaneously the
resultant frequency is xO.Ol and with all buttons
out x200kHz.
2. Frequency Dial: Calibrated from 1to 10 with an additional 0.1
marking and is used in conjunction with the
Frequency Range Switch to set the output
frequency
.

3. CONTROLS AND THEIR FUNCTIONS (continued)
3.4 Signal Source Controls; (cont'd)
3. Function Selector:
4. Amplitude Control:
5.DC Offset/Ramp
Frequency Control;
6. Symmetry Switch:
7. Ramp Amplitude/
Symmetry Control:
8. AM on-off Switch:
9. AM Input Socket:
10. FM Input socket:
11. 0-1 OV Output
Terminal:
Three outputs are available by selection of the correct
button, sine, square or triangle.
Continuously variable control varies output from
0-10 Volts peak to peak.
This control varies the Ramp Frequency. When the
knob is pulled out, the DC level of the Function
Gkenerator output can also be set to >±5V with
respect to ground.
The three position slide switch provides, either
extension of the 4ve or -ve going signal, or
waveforms with a1:1 symmetry.
This control has adual function.
(a) It varies the output amplitude of the Ramp
Generator.
(b) When the Symmetry Switch selects either +ve
or -ve slope extension it adjusts the Magnitude
of the extension.
This switch connects an amplitude modulator into the
circuit so that the output selected by the previous
controls can be varied in amplitude by asuitable
control voltage.
When the AM switch Is 'ON' a+ve voltage introduced
to the socket will decrease the output and a-ve
voltage increase the output.
The output frequency of the generator can be controlled
by connecting avoltage to the FM input socket. A
+ve voltage will increase the frequency above that set
by the Frequency Dial and anegative voltage will
decrease the frequency.
0to lOV p-p of the selected frequency and amplitude
is available at an output impedance of 600Q.
12. 0-1 VOutput
Terminal: 0.01 to l.OV p-p of the selected frequency and
amplitude is available at an output impedance of 600Q.
13. TTL Output
Terminal; ASquare wave output from OV to >f3V is always
available at this point.
2603B

3. CONTROLS AND THEIR FUNCTIONS (continued)
3.4 Signal Source Controls (Cont'd)
14. Ramp Output: 0to +10V Linear Ramp is available at an output
impedance of 600Q.
3.5 Amplifier Section Controls:
15. Power Amp/Bi-Polar/ Position of this switch provides the user with either
+5V Power Supply aPower Amplifier or avariable +15V to -15V
Switch: Supply or afixed +5V Supply.
16. Voltage Control /bi-
polar Power Supply:
With the Bi-Polar Supply in operation, rotation of
this control changes the output voltage over a
±15V range as indicated on the front panel.
17. Power Amplifier Input These terminals accept input signals for the
Terminals: Power Amplifier. When not in use, the blue terminal
becomes open circuit.
18. Power Amp/Bi-Polar/ The output of either the Power Amplifier or
+5V Power Supply the Power Supplies appears here.
Output Terminals:
19. Voltage/Operational
Amplifier Input
Terminals:
An Inverting (-ve) and aNon-Inverting (+ve)
input is provided for both functions of the amplifier.
20. Voltage/Operational
Amplifier Output
Terminal:
The output of either the Voltage Amp., or the
Operational Amp. is available here.
21. Voltage Amplifier Varies the gain from 1(Odb) to 100 (40db).
Gain Control: When turned maximum anti-clockwise, the feed-
back networks are removed converting the
amplifier to an Operational Amplifier.
3.6 Power Supply Section Controls:
22. -1 -15V Voltage
Control:
Rotation of this control provides acontinuously
variable output voltage from approx. -1to -15V
from the:-
23. -1*’-15V Output
Terminal: The required load is connected between this
terminal and the OV terminal which is the common
return to the:-
24. +1^+15V Output
Terminal
.
25. +1^+15V Voltage Provides acontinuously variable output voltage
Control: from approx. +1 to +15V.
603B 3-3

3. CONTROLS AND THEIR FUNCTIONS (continued)
3.6 Power Supply Section Controls: (Cont'd)
26. OV to Earth, Link -
27. 6.3V-0-6.3V AC
Output Terminals;
Is provided so that the common return of the
two supplies can be grounded. However,
either output terminal can be grounded
giving up to +or -30V.
Are the outlets for acentre-tapped winding
on the power transformer. The winding
is insulated from all other terminals and may
be taken to ±200V with respect to ground.
28. 0*'+200V Voltage Control; gives continuously variable adjustment of
the output voltage from OV to +200V.
29. 0^+200V Output
Terminals: The negative terminal is grounded and the
positive terminal supplies 0to +200V output.
30. Power ON/OFF Switch; AD. P. S.T. ,switch connects the mains to
the power transformer providing power for
the entire instrument. When power is
being applied to the unit the:-
31. Power Indicator: Lights up giving avisual indication that the
unit is operating.
3-4E 603B

4. OPERATION:
DESCRIPTION: PARAGRAPH PAGE
GENERAL 1,2 4-2
POWER TRANSFORMER AND AC FUSE 34-2
FUNCTION GENERATOR .44-2
FUNCTION GENERATOR DC OFFSET 44-3
FUNCTION GENERATOR SYMMETRY 44-3
FUNCTION GENERATOR FREQUENCY SWEEP 44-4
FUNCTION GENERATOR A.M. 44-5
POWER AMPLIFIER 54-5
BI-POLAR POWER SUPPLY 64-6
+5V FIXED SUPPLY 74-6
VOLTAGE AMPLIFIER 84-7
OPERATIONAL AMPLIFIER 94-7
+AND -15V VARIABLE POWER SUPPLIES 10 4-9
6.3V AC OUTPUT 11 4-10
0--200V VARIABLE POWER SUPPLY 12 4-11
603B 4-1

4. OPERATION (continued)
4.1
The purpose of this section is to outline the use of each separate function of
Model BWD 603B. For usage requiring interconnection between sections refer to
APPLICATION, SECTION 5'.
4.2
Throughout this section and the following section, drawings of the front panel and
its controls are used to describe settings of switches and knobs.
(a) Where apush button switch is shown, ©j that switch should be depressed.
Otherwise the button should be released.
(b) The position of knobs is shown by an arrow on the front of the knob.
The panel control should be aligned so that the arrow points in the
approximate direction as the drawing.
(c)
(d)
(e)
(f)
Where no arrow appears on the drawing of aparticular knob, the position
of that control has no effect on the operation.
The position of the Frequency Dial is shown by aligning the number
shown on the drawing, against the vertical line at the top of the dial.
Any inputs are designated thus:-
Outputs are designated thus:-
4.3
Check that the power transformer is connected correctly for the mains supply to
which the unit will be connected. If the connection is incorrect refer to section
2.28.
Check the fuse rating on the rear panel of the unit and replace if necessary.
The 3pin plug may now be inserted into the correct receptacle and power applied
via the front panel Power ON/OFF switch and any external power switch.
4.4
Operation of the Function Generator:
With the controls set as shown below the three waveforms drawn to the right of the
panel can be produced by depressing the indicated push button.
4-2 603B

OPERATION (continued)
I4.
4.4
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*
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1
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I603B
I
Operation of the Function Generator (Cont'd)
The frequency of operation will be approximately IkHz. Variations of the Frequency
Dial enables signals within the frequency range of lOOHz to lOkHz to be generated.
The frequency does not change when the Function Selector is used to produce the
three different waveforms.
The output amplitude can be adjusted via the Amplitude Control from O.IV pp to lOVpp
from the main output terminal, and from O.Ol Vp-p to 1,0V p”p from the 0-1 Voutput
terminal. ATTL compatible output is permanently available from the terminal marked
TTL on the front panel. The phase relationship between the TTL output and the other
waveforms is shown below
Offset voltage can be superimposed on the output waveform by pulling the Offset
Control out until it clicks and then rotating the control either side of the centre
point of its rotation. Pushing the knob back in renders the control in-operative.
By setting the symmetry controls as shown below the effect ofvariable symmetry can
be seen;-
4-3

4. OPERATION (continued)
The symmetry change of the waveform is achieved by increasing the time duration
between alternate half cycles, hence the overall effect is to decrease frequency as
the symmetry ratio changes from 1:1 to either 50:1 or 1:50. The beginning of a
cycle of the square wave switching waveform coincides with the peaks of both
the Sine and Triangle waveforms. Since the symmetry control works on ail three
output waveforms the three waveforms appear as below:-
Setting the controls as shown below/ the frequency of the generator can be swept
over any desired portion of the selected frequency range. The sweep width is
adjusted by the Ramp Amplitude control and the starting frequency by the Frequency
control. To vary the sweep speed adjust the Ramp Frequency control.
Should the Frequency Control and the Ramp Amplitude control be set such that
the upper frequency limit would lie outside the calibrated range, an automatic
frequency limiting circuit will re-set the ramp each time it exceeds the calibrated
frequency limit.
UL
-t
5(- 6.7-
Fdial
_set..to.5_
10 UL
Fdial
set to 9
UL=Upper Frequency
Limit
4-4 603B

OPERATION (continued)
Operation of the Function Generator (continued)
I
4
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I603B
If it is required to control the frequency with on external voltage, the lead from
the RAMP output can be disconnected and the external voltage fed into the
F.M. input socket. The voltage/frequency relationship is shown by the graph
on the opposite page, but no upper limit indication is available.
To show the effect of 50Hz sinewave modulation, connect the 6.3V AC source
to the A.M. input as shown to produce the waveform shown below:-
nm
Operation of the Power Amplifier;
Set the controls as shown below:-
4-5

4. OPERATION (continued)
Operation of fhe Power Amplifier (Cont'd)
Connect the load where indicated. An input signal can be obtained either
externally or from the output of the Function Generator. NOTE: that an input
of ±1.5V will give an output of ±15V which is the maximum specified output,
however, if the load impedance is low, the current may exceed ±1 Ampere and
the automatic overload will operate producing adistorted output waveform. To
produce an audible output aspeaker may be connected as aload.
Operation of the Bi-Polar Power Supply:
Set the controls as shown below and connect the load across the output terminals.
MINI-LAB
f
The required output voltage can be set using the Output Voltage Control. For
accurate voltage setting an external meter or DVM should be connected across
the output terminals.
Operation of the -t5V Fixed Power Supply:
Set the controls as shown below and connect the load across the output terminals.
The output voltage will lie between 4.9 and 5.1V from a0to 1amp load.
MINI-LAB I
4-6

4. OPERATION (continued)
4.8Operation of the Voltage Amplifier ;
Set the gain control to xl but ensure the control is not switched to 'Operational
fc. lA ,,ja ,
IBy varying the Gain Control the gain can be adjusted from xl to xlOO.
NOTE: that the input signal will need to be very small for again of 100,
i.e. if the input voltage is ±100mV the output voltage will be ±10V. The
xO.l output of the Function Generator will give an output from lOmV to IV p~p,
which is suitable for demonstrating the amplifier. NOTE: When using the
amplifier, ground the unused input signal.
4.9Operation of the Operational Amplifier :
Set the Voltage Amplifier Gain control to maximum anti-clockwise ensuring that
the rotary switch is switched to 'OP AMP'. The resulting amplifier has open
circuit inputs and no negative feedback, giving it again of approximately lOOdb
(100,000). For most practical purposes this gain can be considered to be infinite,
making the effective gain of any practical circuits dependent on external
components. The following circuits can be constructed using the Operational
Amplifier and afew external components.
603B
a) VOLTAGE FOLLOWER
1/P Or ‘^OUT
-O 0/p
"IN
b) NON-INVERTING AMPLIFIER
iRF
I
•iHizi-
I/P o-cz>
10K —oo/p
c) INVERTING AMPLIFIER
iRF
Ri
I/P 0-0 OO/p
R|in >100 Mn
^CXJT 50ft
Ay =1+RF
RI
Ay =-RF
RI 4-7