APPROVED PRODUCT
C9812
Low EMI Clock Generator for Intel
810E Chipset Systems
SDATA IS OUTPUT PIN
SDATA IS INPUT PIN
ACK
ACK
COMMAND BYTE
(DON'TCARE)
1
1
0
1
0
0
1
0
SDATA
MSB
LSB
SCLK
START CONDITION
8
CONTINUED
ACK
COUNT BYTE
(DON'TCARE)
BYTE 0
(VALID DATA)
ACK
BYTE N (LAST
VALID DATA)
ACK
CONTINUED
8
8
8
STOP CONDITION
Figure 7
SMBUS Communications Waveforms
Test and Measurement Condition
Output under Test
Probe
Load Cap
3.3V signals
tDC
-
-
-
2.5V signals
tDC
-
3.3V
2.5V
2.4V
2.0V
1.25V
1.5V
0.4V
0V
0.4V
0V
Tr
Tf
Tr
Tf
Fig.8
Cypress Semiconductor Corporation
525 Los Coches St.
Milpitas, CA 95035. Tel: 408-263-6300, Fax: 408-263-6571
http://www.cypress.com
Document#: 38-07053 Rev. **
05/03/01
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