8XC198

AC CHARACTERISTICS

The 87C198 will meet these specifications

Symbol

Description

Min

Max

Units

Notes

Frequency on XTAL1 12 MHz

35

12

MHz

(Note 1)

Frequency on XTAL1 16 MHz

35

16

MHz

(Note 1)

833

286

ns

625

286

ns

ALE Cycle Time

ns

(Note 3)

ALE High Period

ns

Address Setup to ALE Falling Edge

ns

Address Hold after ALE Falling Edge

ns

ALE Falling Edge to RD Falling Edge

ns

RD Low Period

ns

(Note 3)

RD Rising Edge to ALE Rising Edge

ns

(Note 2)

RD Low to Address Float

5

ns

ALE Falling Edge to WR Falling Edge

ns

Data Stable to WR Rising Edge

ns

(Note 3)

WR Low Period

ns

(Note 3)

Data Hold after WR Rising Edge

ns

WR Rising Edge to ALE Rising Edge

ns

(Note 2)

INST Hold after WR Rising Edge

ns

INST Hold after ALE Rising Edge

ns

INST Hold after RD Rising Edge

ns

AD8 – 15 Hold after WR Rising Edge

ns

AD8 – 15 Hold after RD Rising Edge

ns

NOTES

1 Testing performed at 35 MHz However the part is static by design and will typically operate below 1 Hz

2 Assuming back-to-back bus cycles

10