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--- university:courses:electronics:electronics-lab-nr [24 Jul 2017 16:17] – change amplitude value to peak-peak Antoniu Miclaus
+++ university:courses:electronics:electronics-lab-nr [11 Jan 2021 11:02] (current) – Fixed bad link for OP482 Ioana Chelaru
@@ Line 50: / Line 50: @@
 Open the voltage supply control and the voltmeter instrument windows from the Scopy software. A DMM, if available, could be useful to more accurately measure the DC voltages in the circuit than the Scopy voltmeter instrument.
+{{ :university:courses:electronics:anr_f2bb.png? |}}
+<WRAP centeralign> Figure 3 LED based volt regulator breadboard connections </WRAP>
 =====Procedure:=====
 Turn on both the positive and negative power supplies. Observe the two voltages at -V<sub>REF</sub>, pins 8 and 14 of the op amp and at +V<sub>REF</sub> on the LED.
+{{ :university:courses:electronics:anr_f2ss.png?600 |}}
+<WRAP centeralign> Figure 4 Scopy voltmeter</WRAP>
 =====Questions:=====
@@ Line 65: / Line 71: @@
 {{ :university:courses:electronics:anr_f3.png?600 |}}
-<WRAP centeralign> Figure 3, NPN shunt band-gap reference example </WRAP>
+<WRAP centeralign> Figure 5 NPN shunt band-gap reference example </WRAP>
 =====Hardware setup:=====
 The setup is the same as step 1.
+{{ :university:courses:electronics:anr_f6.png? |}}
+<WRAP centeralign> Figure 6 LED based volt regulator example </WRAP>
 =====Procedure:=====
@@ Line 77: / Line 86: @@
 ====Testing supply headroom====
-To test the headroom requirements for +V<sub>DD</sub>, disconnect the fixed positive power supply from +V<sub>DD</sub> and remove any supply decoupling capacitors. Be sure to turn off the power supplies before making any changes or additions to your breadboard. Now connect +V<sub>DD</sub> to AWG 1. Set AWG 1 to trapezium (trapezoid)  waveform at 100 Hz. Set the amplitude to 5V with a 2.5V offset for a 0 to +5V swing. Connect scope channel 1 to the output of AWG1 and connect scope channel 2 to -V<sub>REF</sub> of the first example circuit at pin 14 of the OP482. Use the oscilloscope instrument in the XY mode, scope channel for X and scope channel 2 for Y. Start AWG 1 and turn on the fixed negative 5V  power supply. Record the minimum +V<sub>DD</sub> voltage where -V<sub>REF</sub> starts to remain constant at -1.25V.
+To test the headroom requirements for +V<sub>DD</sub>, disconnect the fixed positive power supply from +V<sub>DD</sub> and remove any supply decoupling capacitors. Be sure to turn off the power supplies before making any changes or additions to your breadboard. Now connect +V<sub>DD</sub> to AWG 1. Set AWG 1 to trapezium (trapezoid)  waveform at 100 Hz. Set the amplitude to 5V peak-to-peak with a 2.5V offset for a 0 to +5V swing. Connect scope channel 1 to the output of AWG1 and connect scope channel 2 to -V<sub>REF</sub> of the first example circuit at pin 14 of the OP482. Use the oscilloscope instrument in the XY mode, scope channel for X and scope channel 2 for Y. Start AWG 1 and turn on the fixed negative 5V  power supply. Record the minimum +V<sub>DD</sub> voltage where -V<sub>REF</sub> starts to remain constant at -1.25V.
-To test the headroom requirements for -V<sub>SS</sub>, reconnect +V<sub>DD</sub> to the fixed positive power supply. Disconnect the fixed negative power supply from -V<sub>SS</sub> and remove any supply decoupling capacitors. Now connect -V<sub>SS</sub> to AWG 1. Set the amplitude to 5V with a -2.5V offset for a 0 to -5V swing. Start AWG 1 and turn on the fixed positive 5V  power supply. Repeat your measurements of pins 14 of the OP482 recording the lowest value for -V<sub>SS</sub> where the reference voltage is constant.
-=====Questions:=====
+To test the headroom requirements for -V<sub>SS</sub>, reconnect +V<sub>DD</sub> to the fixed positive power supply. Disconnect the fixed negative power supply from -V<sub>SS</sub> and remove any supply decoupling capacitors. Now connect -V<sub>SS</sub> to AWG 1. Set the amplitude to 5V peak-to-peak with a -2.5V offset for a 0 to -5V swing. Start AWG 1 and turn on the fixed positive 5V  power supply. Repeat your measurements of pins 14 of the OP482 recording the lowest value for -V<sub>SS</sub> where the reference voltage is constant.
 =====Directions Step 3:=====
@@ Line 90: / Line 96: @@
 {{ :university:courses:electronics:anr_f4.png?600 |}}
-<WRAP centeralign> Figure 4, NPN three terminal band-gap reference example </WRAP>
+<WRAP centeralign> Figure 7 NPN three terminal band-gap reference example </WRAP>
 =====Hardware setup:=====
 The setup is the same as step 1.
+{{ :university:courses:electronics:anr_f8.png? |}}
+<WRAP centeralign> Figure 8 LED based volt regulator example </WRAP>
 =====Procedure:=====
@@ Line 102: / Line 111: @@
 Repeat the supply headroom tests you did in Step 2 for this configuration. Are there any differences?
+<WRAP round download>
+**Resources:**
+  * Fritzing files: [[downgit>education_tools/tree/master/m2k/fritzing/neg_voltage_ref_bb | neg_voltage_ref_bb]]
+  * LTspice files: [[downgit>education_tools/tree/master/m2k/ltspice/neg_voltage_ref_ltspice | neg_voltage_ref_ltspice]]
+</WRAP>
 ====For further reading:====
@@ Line 110: / Line 124: @@
 [5] [[university:courses:electronics:electronics-lab-7|Activity 7. Zero gain amplifier (BJT)]]\\
 [6] [[university:courses:electronics:electronics-lab-8|Activity 8. Stabilized current source (BJT)]]\\
-[[http://www.analog.com/static/imported-files/data_sheets/OP282_OP482.pdf]] OP482 datasheet
+[[adi>OP482]] datasheet
 Return to Lab Activity [[university:courses:electronics:labs|Table of Contents]]
@@ Line 116: / Line 130: @@
 ====Appendix:====

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