Motorola MC68340 ユーザーズマニュアル

11-22

MOTOROLA

 (See notes (a), (b), (c), and

(d) corresponding to part operation, GND = 0 Vdc, TA = 0 to 70

°

C; see numbered notes;  see Figures 11-15–11-18)

1

CLKOUT Cycle Time

tcyc

119.2

—

59.6

—

40

—

ns

2

Clock Rise or Fall Time

trf

—

20

—

10

—

5

ns

3

2

Clock Input (X1 or SCLK ) Synchronizer Setup
Time

tCS

15

—

8, 5

—

5

—

ns

4

Clock Input (X1 or SCLK ) Synchronizer Hold
Time

tCH

30

—

15

—

8

—

ns

5

TxD Data Valid from  CLKOUT High

tVLD

0.5 t cyc

Max

6

X1 Cycle Time

tX1

2.25 t cyc

Min

7

X1  High or Low Time

tX1HL

0.55 t cyc + 0.75(tCS + tCH)

Min

8

SCLK High or Low Time, Asynchronous (16x)
Mode

tAHL

tcyc + tCS + tCH

Min

9

1

SCLK High Time, Synchronous (1x) Mode

tSH

tcyc(Gx) + tCS(Gx) + tCH(Gx)

Min

10

SCLK Low Time, Synchronous (1x) Mode

tSL

greater of

({1.5tcyc(Tx) + tCS(Tx) + tVLD(Tx)} +

0.5tcyc(Rx) + tCS(Rx) + tCH(Rx)})

or

tSH

Min

11

TxD Data Valid from SCLK Low, Synchronous
(1x) Mode

tT 

× 

D

1.5tcyc(Tx) +

tCS(Tx) + tVLD(Tx)

Max

12

RxD Setup Time to SCLK High, Synchronous
(1x) Mode

tR 

× 

S

0.5tcyc(Rx) + tCS(Rx) + tCH(Rx)

Min

13

RxD Hold Time from SCLK High, Synchronous
(1x) Mode

tR 

× 

H

0.5tcyc(Rx) + tCS(Rx) + tCH(Rx)

Min

NOTES:

(a) The electrical specifications in this document for both the 8.39 and 16.78 MHz @ 3.3 V 

±

0.3 V are preliminary

and apply only to the appropriate MC68340V low voltage part.

(b) The 16.78-MHz specifications apply to the MC68340 @ 5.0 V 

±

5% operation.

(c) The 25.16 MHz @ 5.0 V 

±

5% electrical specifications are preliminary.

(d) For extended temperature parts T A = –40 to +85

°

C. These specifications are preliminary.

1.

Asynchronous operation numbers take into account a receiver and transmitter operating at different clock
frequencies. (Rx) refers to receiver value. (Tx) refers to transmitter value. (Gx) refers to the value that is greater,
either receiver or transmitter.

2.

Specification #3 for 16.78 MHz @ 3.3 V 

±

0.3 V will be 8 ns.

 

CLKOUT

TxD

1

5

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Freescale Semiconductor, Inc.

For More Information On This Product,

   Go to: www.freescale.com

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