LM3S2637 Datasheet, PDF (641/678 Pages) Texas Instruments – Stellaris® LM3S2637 Microcontroller

Stellaris^® LM3S2637 Microcontroller
Table 20-21. I²C Characteristics (continued)
Parameter
No.
Parameter Parameter Name
Min Nom Max
Unit
I4^a
t_DH
Data hold time
2
-
-
system clocks
I5^c
t_SFT
I2CSCL/I2CSDA fall time (V_IH =2.4 V
-
9
10
ns
to V _IL =0.5 V)
I6^a
t_HT
Clock High time
24
-
-
system clocks
I7^a
t_DS
Data setup time
18
-
-
system clocks
I8^a
t_SCSR
Start condition setup time (for repeated 36
-
-
system clocks
start condition only)
I9^a
t_SCS
Stop condition setup time
24
-
-
system clocks
a. Values depend on the value programmed into the TPR bit in the I²C Master Timer Period (I2CMTPR) register; a TPR
programmed for the maximum I2CSCL frequency (TPR=0x2) results in a minimum output timing as shown in the table
above. The I ²C interface is designed to scale the actual data transition time to move it to the middle of the I2CSCL Low
period. The actual position is affected by the value programmed into the TPR; however, the numbers given in the above
values are minimum values.
b. Because I2CSCL and I2CSDA are open-drain-type outputs, which the controller can only actively drive Low, the time
I2CSCL or I2CSDA takes to reach a high level depends on external signal capacitance and pull-up resistor values.
c. Specified at a nominal 50 pF load.
Figure 20-15. I²C Timing
I2
I6
I5
I2CSCL
I1
I4
I7
I8 I3
I9
I2CSDA
20.2.11 Analog Comparator
Table 20-22. Analog Comparator Characteristics
Parameter Parameter Name
Min
V_OS
Input offset voltage
-
V_CM
Input common mode voltage range
0
C_MRR
Common mode rejection ratio
50
T_RT
Response time
-
T_MC
Comparator mode change to Output Valid
-
Nom
±10
-
-
-
-
Table 20-23. Analog Comparator Voltage Reference Characteristics
Parameter
R_HR
R_LR
A_HR
A_LR
Parameter Name
Resolution high range
Resolution low range
Absolute accuracy high range
Absolute accuracy low range
Min
Nom
-
V_DD/31
-
V_DD/23
-
-
-
-
Max
±25
V_DD-1.5
-
1
10
Max
-
-
±1/2
±1/4
Unit
mV
V
dB
µs
µs
Unit
LSB
LSB
LSB
LSB
June 18, 2012
641
Texas Instruments-Production Data