MIKROE-957 mikroElektronika, MIKROE-957 Datasheet - Page 56

• 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

10.1 Brief theory and motivation
LDO is used to produce regulated voltage for high efficiency low noise applications.
Please view the recorded lectures at
regulators. In case of DC-DC converter switching takes place (as shown by PWM
waveform) and switching is a source of noise but in LDO no switching takes place
hence it is used as voltage regulator in low noise high efficient systems. As shown
in the circuit below LDO uses PMOS along with OP-Amp so that power dissipation in
OP-Amp is minimal and efficiency is high. The regulated output voltage is given by
V
V
10.2 Specifications
Generate 3V output when input voltage is varying from 4V to 5V.
page 56
dV V
dV
dI
0
0
=
0
0
0
The goal of this experiment is to design a Low Dropout regulator using
general purpose OP-Amp and PMOS and study its characteristics with
extension to study characteristics of TPS7250 IC. We aim to design a
linear voltage regulator with high efficiency which is used in low noise high
efficiency applications.
V
0
ref
_
1
+
R R
2
Goal of the experiment
R
1
i .
Vref
Figure 10.1: Low Dropout Regulator (LDO)
R
1
V
R
UN
[23]
2
for a detailed description of voltage
R
V
L
O
= Vref [1+
R
R
2
1
]
10.3 Measurements to be taken
1
2
3
4
Output Characteristics - Measure the load regulation of the system. Load regulation
is given by
Transfer Characteristics - Measure the line regulation of the system. Line regulation
is given by
Measure the ripple rejection by applying the ripple input voltage and measuring
the output ripple voltage.
Measure the output impedance of the LDO, which is given by
the sample output of load regulation and line regulation in Figure 10.2.
S.No.
Table 10.1: Variation of Load Regulation with Load Current in an LDO
1
2
3
4
V
dV V
V
V
dV V
V
Figure 10.2: A regulator circuit and its simulated
dV
dV
dI
dI
0
0
0
0
=
0
=
0
0
0
outputs - line regulation and load regulation
0
0
R 10k
V
V
0
0
Reference Voltage
ref
ref
when Io is varying from minimum to maximum value.
when
_
_
Z
1
1
1
+
+
R R
V
R R
dV V
V
dV
dI
0
0
2
2
=
0
is varying from minimum to maximum value.
0
0
1
V
1
i
i
0
ref
_
1
R
R
+
2
3
R R
10k
10k
2
+
Analog System Lab Kit PRO
V
1
V
1
i
F1
R
R
6
4
10k
10k
Output Voltage
D
V
V
dV V
R
dV
dI
1
0
0
5
=
0
0
0
. We have shown
2k
V
0
ref
_
1
+
R R
2
1
i