Basic Elec. Engr Basic Elec. Engr. Lab . Lab ECS 204 ECS 204 - PowerPoint PPT Presentation

Basic Elec. Engr Basic Elec. Engr. Lab . Lab ECS 204 ECS 204 Asst. Prof. Dr. Prapun Suksompong prapun@siit.tu.ac.th Operational amplifier • Lab 7 Inverting amplifier • Summing Amplifier • 1

Op-Amp 741  OP erational AMP lifier V+ , Positive (Not connected) power supply Noninverting (1) Offset null NC (8) (7) input (2) Inverting (3) V+ (7) (6) input (3) Noninverting + Output (6) (2) Output input (4) Inverting (4) V- Offset null (5) V- , Negative input power supply 2

Placing op amps on the proto-board  Plug in op amp chips so that they straddle the troughs on the proto board.  In this way, each pin is connected to a different hole set. 3

Powering the op amp  The op amp must be powered by voltage supplies.  These supplies are often ignored in op amp circuit diagrams for the sake of simplicity. 4

Powering the op amp -5 V GND +5 V 5

Op amp tester 6

Part A: Inverting Amplifier R   V F V. o i R R 7

Part A: Inverting Amplifier R   V F V. o i R R 8

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Part A: Inverting Amplifier 11

Demo: Clipping 12

Part B: Summing Am Amplifier plifier  Note that you will need 4 DC Voltage Sources in this part. 1 1 F 1 2 2 2 o   R R    F F V V V .   o 1 2 R R   1 2 13