Input test waveforms and measurement levels, Output test load, Ac waveforms – Rainbow Electronics AT45DB161D User Manual

Page 32: Output test load 21. ac waveforms

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32

3500O–DFLASH–11/2012

AT45DB161D

19.

Input Test Waveforms and Measurement Levels

t

R

, t

F

< 2ns (10% to 90%)

20.

Output Test Load

21.

AC Waveforms

Six different timing waveforms are shown on

page 32

. Waveform 1 shows the SCK signal being low when CS

makes a high-to-low transition, and waveform 2 shows the SCK signal being high when CS makes a high-to-low
transition. In both cases, output SO becomes valid while the SCK signal is still low (SCK low time is specified as
t

WL

). Timing waveforms 1 and 2 conform to RapidS serial interface but for frequencies up to 66MHz. Waveforms 1

and 2 are compatible with SPI Mode 0 and SPI Mode 3, respectively.

Waveform 3 and waveform 4 illustrate general timing diagram for RapidS serial interface. These are similar to
waveform 1 and waveform 2, except that output SO is not restricted to become valid during the t

WL

period. These

timing waveforms are valid over the full frequency range (maximum frequency = 66MHz) of the RapidS serial case.

21.1

Waveform 1 – SPI Mode 0 Compatible (for frequencies up to 66MHz)

AC

DRIVING

LEVELS

AC

MEASUREMENT

LEVEL

0.45V

1.5V

2.4V

DEVICE

UNDER

TEST

30pF

CS

SCK

SI

SO

t

CSS

VALID IN

t

H

t

SU

t

WH

t

WL

t

CSH

t

CS

t

V

HIGH IMPEDANCE

VALID OUT

t

HO

t

DIS

HIGH IMPEDANCE

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