MIKROE-957 mikroElektronika, MIKROE-957 Datasheet - Page 88

• Manufacturer Part Number: MIKROE-957
• Description: Other Development Tools ASLK PRO ANALOG DEVELOPMENT SYSTEM
• Manufacturer: mikroElektronika

Specifications of MIKROE-957

• Rohs: yes
• Product: Analog System Lab Kit PRO
• Tool Is For Evaluation Of: TL082, MPY634
• Operating Supply Voltage: 2.5 V to 5.5 V
• Description/function: Analog Lab Kit for Undergraduate Engineering
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C

C.1 Introduction
In any analog lab, an oscilloscope is required to display
waveforms at different points in the circuit under
construction in order to verify circuit operation and, if
necessary, redesign the circuit. High-end oscilloscopes
are needed for measurements and characterization
in labs. Today, solutions are available to students for
converting a PC into an oscilloscope. These solutions
require some additional hardware to route the analog
signals to the PC for observation; they also require
software that provides the graphical user interface to
convert a PC display into an oscilloscope. Since most
students have access to a PC or laptop today, we have
designed the Analog System Lab such that a PC-based
oscilloscope solution can be used along with ASLK
PRO. We believe this will reduce the dependence of
Figure C.1:
Buffer circuit
needed to
interface an
Analog Signal
to Oscilloscope
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Zin=1M
IVinl<150V
BNC
0.1uF
C
1
R
1M
1
the student on a full-edged lab. In this chapter, we
will review a solution for a PC-based oscilloscope. The
components on the ASLK PRO can be used to build
the interface circuit needed to convert the PC into an
oscilloscope.
One of the solutions for a “PC oscilloscope” is Zelscope
[33]
Microsoft Windows XP. The hardware requirements for
the PC are modest (300+ MHz clock, 64+ MB memory).
It uses the sound card in the PC for converting the
analog signals into digital form. The Zelscope software,
which requires about 1 MB space, is capable of using
the digitized signal to display waveforms as well as
the frequency spectrum of the analog signal. At the
‘line in’ jack of the sound card, the typical voltage
which works on personal computers running
C
20pF
2
47k 1/2W
100pF
C3
R
2
4.7k
R
3
-12V
D
1N914
D
1N914
2
3
+12V
D
1N914
1
R
3k
S
1
4
TI082
27k
R
S
should be about 1 volt AC; hence it is essential to
protect the sound card from over voltages. A buffer
amplifier circuit is required to protect the sound card
from overvoltages. Two copies of such a circuit are
needed to implement a dual-channel oscilloscope. The
buffer amplifier circuit is shown in Figure C.1 and has
been borrowed from [32].
• N ot possible to display DC voltages (due to input
• Low frequency range (10 Hz-20 kHz)
• Measurement is not very accurate
Limitations
capacitor of sound card blocks DC)
100k
R
6
Analog System Lab Kit PRO
IVoutl<12V
RCA