MCP3421
DS22003E-page 24
2009 Microchip Technology Inc.
TABLE 5-4:
I2C SERIAL TIMING SPECIFICATIONS
Electrical Specifications: Unless otherwise specified, all limits are specified for T
A = -40 to +85°C,
VIN+ = VIN- = VREF/2, VSS = 0V, VDD = +2.7V to +5.0V.
Parameters
Sym
Min
Typ
Max
Units
Conditions
Standard Mode (100 kHz)
Clock frequency
fSCL
—
100
kHz
Clock high time
THIGH
4000
—
ns
Clock low time
TLOW
4700
—
ns
SDA and SCL rise time
TR
—
1000
ns
SDA and SCL fall time
TF
—
300
ns
START condition hold time
THD:STA
4000
—
ns
START (Repeated) condition
setup time
TSU:STA
4700
—
ns
Data hold time
THD:DAT
0
—
3450
ns
Data input setup time
TSU:DAT
250
—
ns
STOP condition setup time
TSU:STO
4000
—
ns
Output valid from clock
TAA
0
—
3750
ns
Bus free time
TBUF
4700
—
ns
Time between START and
STOP conditions.
Fast Mode (400 kHz)
Clock frequency
TSCL
—
400
kHz
Clock high time
THIGH
600
—
ns
Clock low time
TLOW
1300
—
ns
SDA and SCL rise time
TR
20 + 0.1Cb
—
300
ns
SDA and SCL fall time
TF
20 + 0.1Cb
—
300
ns
START condition hold time
THD:STA
600
—
ns
START (Repeated) condition
setup time
TSU:STA
600
—
ns
Data hold time
THD:DAT
0
—
900
ns
Data input setup time
TSU:DAT
100
—
ns
STOP condition setup time
TSU:STO
600
—
ns
Output valid from clock
TAA
0
—
1200
ns
Bus free time
TBUF
1300
—
ns
Time between START and
STOP conditions.
Note 1: This parameter is ensured by characterization and not 100% tested.
2: This specification is not a part of the I2C specification. This specification is equivalent to the Data Hold
Time (THD:DAT) plus SDA Fall (or rise) time: TAA = THD:DAT + TF (OR TR).
3: If this parameter is too short, it can create an unintended Start or Stop condition to other devices on the
bus line. If this parameter is too long, Clock Low time (TLOW) can be affected.
4: For Data Input: This parameter must be longer than t
SP. If this parameter is too long, the Data Input Setup
(TSU:DAT) or Clock Low time (TLOW) can be affected.
For Data Output: This parameter is characterized, and tested indirectly by testing TAA parameter.