SRAMStatic Read Only Memory

Curiosity . . .

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Working of Binary Cell (B.C.)

• Binary Cell is used to store 1 bit information.• R S Flip Flop is used to store that bit.• Binary Cell is Enabled only when Select=1 and if Select=0 than B.C. is

disable.• And when Select=1 than all three AND gates in circuit are partial ON• When select=1 and

– In R/W if it is 1 than it will read the value.

If it is 0 than it will write the value on it.• There is a Special AND gate(A3) tri-state gate (Gate having three states)

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4X3 SRAM (Read Operation)

BC BC BC

BC BC BC

BC BC BC

BC BC BC

D2 D1 D0Din

Dout

D2 D1 D0R/W

2 X 4Decoder

0011

10 01

1 = Read0 = Write

00

01

10

11

a1 a2 a3

b1 b2 b3

c1 c2 c3

d1 d2 d3

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4X3 SRAM (Write Operation) D2 D1 D0

Din

D2 D1 D0R/W1 = Read0 = Write

BC BC BC

BC BC BC

BC BC BC

BC BC BC

Dout

2 X 4Decoder

0011

10 01

00

01

10

11

x zy

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DRAMDynamic Read Only

Memory

Sharp

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ROMRead Only Memory

Adventure

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ROM

2X4 Decoder

D2 D1 D0Dout

011

101

1

1

00

01

10

11

Wired OR

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ROM

2X4 Decoder

D2 D1 D0Dout

001

010

1

1

00

01

10

11

After burning required diodes

RequiredSequence 010 011 101 001

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This diode is reverse biased and therefore the flow of current is only the following direction

Diagrammatically representation of diode

But the following possibility is not present over this circumstances like shown in below figure

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Magnetic memories

Magnetic Tape

Floppy disk

magnetic drum

COOL

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Magnetic Tape

Power of Colors

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COIL

+ -

Amplifier

Magnetic Tape

Output waves

Ferric oxide layer (Iron Practical)

S N

Diagrammatical representation of a single particle

0 1

HeadTail

to strengthening in the signal (voltage or current) we use Amplifier

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FLOPPY DISK

Simplicity

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Cleaning Pads

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contd…contd…