AT45DB021A View Datasheet(PDF) - Atmel Corporation
Part Name
Description
MFG CO.
'AT45DB021A' PDF : 28 Pages View PDF
Input Test Waveforms and
Measurement Levels
AC
DRIVING
LEVELS
2.4V
0.45V
2.0 AC
MEASUREMENT
0.8 LEVEL
tR, tF < 5 ns (10% to 90%)
Output Test Load
DEVICE
UNDER
TEST
30 pF
AC Waveforms
Two different timing diagrams are shown below. 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. Both
waveforms show valid timing diagrams. The setup and hold
times for the SI signal are referenced to the low-to-high
transition on the SCK signal.
Waveform 1 shows timing that is also compatible with SPI
Mode 0, and Waveform 2 shows timing that is compatible
with SPI Mode 3.
Waveform 1 – Inactive Clock Polarity Low and SPI Mode 0
CS
tCSS
tWH tWL
tCSH
SCK
tV
HIGH IMPEDANCE
SO
tHO
VALID OUT
tSU
tH
SI
VALID IN
tCS
tDIS
HIGH IMPEDANCE
Waveform 2 – Inactive Clock Polarity High and SPI Mode 3
CS
SCK
SO
SI
tCSS tWL tWH
tV
HIGH Z
tSU
tHO
VALID OUT
tH
VALID IN
tCSH
tCS
tDIS
HIGH IMPEDANCE
12
AT45DB021A
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