ROM details

• Similar to a PLA but with a fully decoded AND array
• Completely flexible OR array (unlike a PAL)
• Extremely dense: One transistor per stored bit

decoder

0 n-1

Address

2 -1

n

0

+5V

Bit lines: Normally pulled high through resistor. If transistor stores a zero, then

line pulls low when row is selected

j

i

Only one word line

is active at any time

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