IMX35 Datasheet, PDF (68/148 Pages) Power-One – 35 Watt DC-DC Converters

4.9.11 I²C AC Electrical Specifications
This section describes the electrical characteristics of the I²C module.
4.9.11.1 I²C Module Timing
Figure 44 depicts the timing of the I²C module. Table 49 lists the I²C module timing parameters.
IC10
IC11
IC9
I2DAT
IC2
I2CLK
IC8
IC4
IC7
IC3
START
IC10
IC11
START
IC6
IC5
IC1
Figure 44. I²C Bus Timing Diagram
Table 49. I²C Module Timing Parameters
STOP
START
Standard Mode
Fast Mode
ID
Parameter
Unit
Min.
Max.
Min.
Max.
IC1 I2CLK cycle time
10
—
2.5
— μs
IC2 Hold time (repeated) START condition
4.0
—
0.6
— μs
IC3 Set-up time for STOP condition
IC4 Data hold time
4.0
—
0¹
3.45²
0.6
— μs
0¹
0.9² μs
IC5 HIGH Period of I2CLK Clock
4.0
—
0.6
— μs
IC6 LOW Period of the I2CLK Clock
4.7
—
1.3
— μs
IC7 Set-up time for a repeated START condition
IC8 Data set-up time
4.7
—
250
—
0.6
100³
— μs
— ns
IC9 Bus free time between a STOP and START condition
4.7
—
1.3
— μs
IC10 Rise time of both I2DAT and I2CLK signals
—
1000
—
300 ns
IC11 Fall time of both I2DAT and I2CLK signals
—
300
—
300 ns
IC12 Capacitive load for each bus line (C_b)
—
400
—
400 pF
1 _{A device must internally provide a hold time of at least 300 ns for the I2DAT signal in order to bridge the undefined region of}
the falling edge of I2CLK.
2 _{The maximum hold time has to be met only if the device does not stretch the LOW period (ID IC6) of the I2CLK signal.}
3 _{A fast-mode I}2_{C-bus device can be used in a standard-mode I}2_{C-bus system, but the requirement of set-up time (ID IC7) of}
250 ns must then be met. This will automatically be the case if the device does not stretch the LOW period of the I2CLK signal.
If such a device does stretch the LOW period of the I2CLK signal, it must output the next data bit to the I2DAT line
max_rise_time (ID No IC10) + data_setup_time (ID No IC8) = 1000 + 250 = 1250 ns (according to the Standard-mode I²C-bus
specification) before the I2CLK line is released.
i.MX35 Applications Processors for Automotive Products, Rev. 6
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Freescale Semiconductor