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Version 1 – May 2014

3/13

4 Timing Specifications

4.1 Sensor System Timings

Default conditions of 25 °C and 1.8 V supply voltage apply to values the table below, unless otherwise stated. Max. values are

measured at -30°C and 1.98V supply voltage.

Parameter

Symbol

Conditions

Min.

Typ.

Max.

Units Comments

Power-up time

-

182

239

µs

and sensor entering idle state

Soft reset time

After soft reset.

-

173

230

µs

Time between ACK of soft reset

command and sensor entering

idle state

Measurement duration

-

-

10.8

14.4

ms

Duration for a temperature

Table 4 System timing specifications.

4.2 Communication Timings

Default conditions of 25 °C and 1.8 V supply voltage apply to values in the table below, unless otherwise stated.

Parameter

Symbol

Conditions

Min.

Typ.

Max.

Units Comments

SCL clock frequency

-

0

-

400

kHz -

Hold time (repeated) START

condition

After this period, the first

clock pulse is generated

0.6

-

-

µs

-

-

1.3

-

-

µs

-

-

0.6

-

-

µs

-

Set-up time for a repeated

START condition

-

0.6

-

-

µs

-

SDA hold time

-

0

-

-

-

-

SDA set-up time

-

100

-

-

ns

-

SCL/SDA rise time

-

20

-

300

ns

-

SCL/SDA fall time

-

20 *

-

300

ns

-

SDA valid time

-

-

-

0.9

µs

-

Set-up time for STOP

condition

-

0.6

-

-

µs

-

Capacitive load on bus line

-

-

-

400

pF

-