lab #2 – power supply. © bob york back to toc 2 © bob york back to toc 3 linear power supply

Lab #2 – Power Supply

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Linear Power Supply

LoadRegulatorFilterRectifierTrans-formerTo AC line

Vmsint

Vout

Vout

Iout

+

-

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Rectifier/Regulator Circuits

+C RVout

Iout

+

-

Transformer Bridge Rectifier

+C RVout

Iout

+

-

Transformer Bridge Rectifier

ActiveRegulator

+C

Vpos+

Center-TappedTransformer

BridgeRectifier Positive

Regulator

CVneg

NegativeRegulator

Common

Vout RUnregulated DC

Voltage-controlled resistor Iout

Vref

VpV

T

Time

Voltage

Charging Discharging

T/2

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Power Transformer Assembly

In-line fuse holder

AC Power cord

Transformer

PrimarySecondary

Power switch

Earth ground 9 VAC

120 VAC

240 VAC

Blue

RedBlack

Black

Yellow

Yellow

9 VAC

Jameco105532

120 VAC

9 VAC

Blue

9 VAC

Black

Black Blue

Blue w/Stripe

StancorP-8691

18VCT @ 1AOn/Off

Fuse

AC power

Earth ground

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Full Schematic

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PC Board

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Separate individual pins for test points

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Rectifier Plus Capacitors

Cathode

18VCT @ 1AOn/Off

Fuse

AC power

Earth ground

GND

C1RL

0.1Ω

C3

+Rect

-Rect

Rs

Vout

Long-lead is “positive”

“-” sign on package indicates “negative” lead

Value and voltage rating printed on package

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LM317 Regulator

“Wiper”

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Scope Grid