Preliminary Data Sheet, Rev. 5

USS-720

Instant USB

September 1999

USB-to-IEEE

1284 Bridge

 

 

 

Timing Characteristics

Timing is specified over the operating range from 0 °C to 70 °C ambient temperature, VDD = 3.0 V to 3.6 V, and VDD5 = 4.75 V to 5.25 V.

All timing is referenced from the rising edge of CLK_LO, with 70 pF output load.

Only DIO is required to meet these input setup and hold times for proper operation. For other inputs, meeting the limit is only required to ensure that the signal will be recognized on the referenced clock edge rather than one period later.

Table 34. Setup and Hold Input Timing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Parameter

Setup Time

 

Hold Time

 

Unit

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DIO Setup and Hold

2.9

 

 

3.4

 

ns

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 35. Clock Characteristics/Miscellaneous Input Timing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Parameter

 

 

Symbol

 

Min

 

Typical

Max

Unit

 

 

 

 

 

 

 

 

 

Frequency of Operation (CLK_LO)

 

f

 

11.976

 

12.000

12.024

MHz

 

 

 

 

 

 

 

 

 

 

Clock Period

 

 

tcyc

 

83.1

 

83.3

83.5

ns

 

 

 

 

 

 

 

 

 

 

Duty Cycle

 

 

 

 

40/60*

%

 

 

 

 

 

 

 

 

 

 

 

 

* The duty cycle applies to any frequency in the specified range.

Table 36. Output Delay Timing

Parameter

Min

Max

Unit

 

 

 

 

PDATA Output Delay

5.3

21.5

ns

 

 

 

 

NUSB_RESET Output Delay

6.5

17.1

ns

 

 

 

 

SUSPEND Output Delay

2.6

34.6

ns

SK Output Delay

6.4

16.0

ns

 

 

 

 

CS Output Delay

75.0

ns

 

 

 

 

DIO Output Delay

3.6

31.6

ns

Table 37. Miscellaneous Output Timing

Parameter

Symbol

Min

Typical

Max

Unit

 

 

 

 

 

 

Frequency of Operation (SK)

f

390

429

476

kHz

 

 

 

 

 

 

Clock Period

tcyc

2.10

2.33

2.56

μs

 

 

 

 

 

 

Duty Cycle

50/50*

%

 

 

 

 

 

 

* The duty cycle applies to any frequency in the specified range.

Lucent Technologies Inc.

5-27

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Image 53
Lucent Technologies USS-720 manual Timing Characteristics, Setup and Hold Input Timing Parameter