SI3452 SILABS [Silicon Laboratories], SI3452 Datasheet - Page 9

• Manufacturer Part Number: SI3452
• Description: QUAD HIGH-VOLTAGE PORT CONTROLLER FOR POE AND POE+ PSES
• Manufacturer: SILABS [Silicon Laboratories]

Table 11. SMBus (I
VDD = 3.0 to 3.6 V
Description
Serial bus clock frequency
SCL high time
SCL low time
SCL, SDA rise time
SCL, SDA fall time
Bus free time
Start hold time
Start setup time
Stop setup time
Data hold time
Data setup time
Time from hardware or soft-
ware reset until start of I
traffic
Delay from event to INT pin
low or from clear-on-read to
INT pin high
Notes:
1. Not production tested (guaranteed by design).
2. All timing references measured at V
3. The Si3452/3 will stretch (pull down on) SCK during the ACK time period if required. The maximum SCL stretching is
10 µsec; so, SCL only needs to be bidirectional for I
SDA
SCL
t
BU F
2
C) Timing Specifications (see Figure 1)
Start Bit
2
C
t
ST H
Symbol
f
t
t
SC L
t
RESET
R_SCL
F_SCL
t
t
t
t
f
t
t
t
SKH
t
t
SCL
SKL
BUF
STH
STS
SPS
INT
DH
DS
D7
IL
Figure 1. I
and V
t
Between START and first low SCL.
R_SCL
Between SCL high and START
IH
Between SCL high and STOP
Between START and STOP
D 6
.
Reset to start condition
t
2
DS
C Timing Diagram
Rev. 1.0
Test Conditions
2
C bus speeds over 50 kHz.
conditions.
condition.
condition.
D5
t
F_SC L
D 4
t
D H
t
SKH
D 3
Min
600
600
600
600
200
200
1.3
1.3
20
20
—
—
0
D0
Typ
—
—
—
—
—
—
—
—
—
—
—
—
—
t
SKL
Si3452/3
t
Stop Bit
SPS
Max
400
300
150
100
—
—
—
—
—
—
—
—
5
Unit
kHz
ms
ms
ns
μs
ns
ns
μs
ns
ns
ns
ns
ns
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