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Temperature sensor characteristics, Ac electrical characteristics: i, C interface – Rainbow Electronics DS2741 User Manual

Page 3

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DS2741

Current Monitor and Accumulator with

Integrated Sense Resistor

_______________________________________________________________________________________

3

TEMPERATURE SENSOR CHARACTERISTICS

(V

CC

= +2.5V to +4.5V, T

A

= -20°C to +70°C, unless otherwise noted.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Temperature Error

±5

°C

AC ELECTRICAL CHARACTERISTICS: I

2

C INTERFACE

(2.5V

≤ V

CC

≤ 4.5V, T

A

= -20°C to +70°C, timing referenced to V

IL(MAX)

and V

IH(MIN)

. See Figure 4.)

PARAMETER SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

SCL Clock Frequency

f

SCL

(Note

5)

0

400 kHz

Bus Free Time Between STOP
and START Conditions

t

BUF

1.3

μs

Hold Time (Repeated) START
Condition

t

HD:STA

0.6

μs

Low Period of SCL

t

LOW

1.3

μs

High Period of SCL

t

HIGH

0.6

μs

Data Hold Time

t

HD:DAT

0

0.9

μs

Data Setup Time

t

SU:DAT

100

ns

START Setup Time

t

SU:STA

0.6

μs

SDA and SCL Rise Time

t

R

(Note

6)

20 +

0.1C

B

300 ns

SDA and SCL Fall Time

t

F

(Note

6)

20 +

0.1C

B

300 ns

STOP Setup Time

t

SU:STO

0.6

μs

SDA and SCL Capacitive
Loading

C

B

(Note

6)

400 pF

Note 1: All voltages are referenced to GND. Currents entering the IC are specified positive and currents exiting the IC are negative.
Note 2: Compensation of the internal sense resistor value for initial tolerance and temperature coefficient of -20°C to +70°C can

reduce the maximum reportable magnitude to 2.5A.

Note 3: Current sampling ceases for 2.5ms every 144ms to allow the ADC to measure temperature.
Note 4: Typical value for t

ERR1

is specified at 3.6V and +25°C, max value is specified for 0°C to +50°C. Max value for t

ERR2

is

specified for -20°C to +70°C.

Note 5: Interface timing shown is for fast-mode (400kHz) operation. This device is also backward compatible with standard-mode

I

2

C timing.

Note 6: C

B

—Total capacitance of one bus line in pF; timing referenced to 0.1 x V

CC

and 0.9 x V

CC

.