Ac electrical characteristics – Rainbow Electronics DS1854 User Manual

Page 4

Advertising
background image

DS1854

Dual Temperature-Controlled Resistors with
Two Monitors

4

_____________________________________________________________________

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Fast mode (Note 9)

0

400

SCL Clock Frequency

f

SCL

Standard mode (Note 9)

0

100

kHz

Fast mode (Note 9)

1.3

Bus Free Time Between STOP and
START Condition

t

BUF

Standard mode (Note 9)

4.7

µs

Fast mode (Notes 9, 10)

0.6

Hold Time (Repeated)
START Condition

t

HD:STA

Standard mode (Notes 9, 10)

4.0

µs

Fast mode (Note 9)

1.3

Low Period of SCL Clock

t

LOW

Standard mode (Note 9)

4.7

µs

Fast mode (Note 9)

0.6

High Period of SCL Clock

t

HIGH

Standard mode (Note 9)

4.0

µs

Fast mode (Notes 9, 11, 12)

0

0.9

Data Hold Time

t

HD:DAT

Standard mode (Notes 9, 11, 12)

0

µs

Fast mode (Note 9)

100

Data Setup Time

t

SU:DAT

Standard mode (Note 9)

250

ns

Fast mode (Note 9)

0.6

Start Setup Time

t

SU:STA

Standard mode (Note 9)

4.7

µs

Fast mode (Note 13)

20 + 0.1C

B

300

Rise Time of Both SDA and SCL
Signals

t

R

Standard mode (Note 13)

20 + 0.1C

B

1000

ns

Fast mode (Note 13)

20 + 0.1C

B

300

Fall Time of Both SDA and SCL
Signals

t

F

Standard mode (Note 13)

20 + 0.1C

B

300

ns

Fast mode

0.6

Setup Time for STOP Condition

t

SU:STO

Standard mode

4.0

µs

Capacitive Load for Each Bus Line

C

B

(Note 13)

400

pF

EEPROM Write Time

t

W

(Note 14)

10

ms

AC ELECTRICAL CHARACTERISTICS

(V

CC

= 3.0V to 5.5V, T

A

= -40°C to +95°C, unless otherwise noted.)

Note 1:

All voltages are referenced to ground.

Note 2:

I/O pins of fast-mode devices must not obstruct the SDA and SCL lines if V

CC

is switched off.

Note 3:

SDA and SCL are connected to V

CC

and all other input signals are connected to well-defined logic levels.

Note 4:

The maximum voltage the MON inputs will read is approximately 2.5V, even if the voltage on the inputs are
greater than 2.5V.

Note 5:

This voltage is defining the maximum range of the analog-to-digital converter and not the maximum
V

CC

voltage.

Note 6:

Absolute linearity is the difference of measured value from expected value at DAC position. The expected value is a
straight line from measured minimum position to measured maximum position.

Note 7:

Relative linearity is the deviation of an LSB DAC setting change vs. the expected LSB change. The expected LSB change
is the slope of the straight line from measured minimum position to measured maximum position.

Note 8:

See the

Typical Operating Characteristics.

Note 9:

A fast-mode device can be used in a standard-mode system, but the requirement t

SU:DAT

> 250ns must then be met. This

is automatically the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the
LOW period of the SCL signal, it must output the next data bit to the SDA line t

RMAX

+ t

SU:DAT

= 1000ns + 250ns = 1250ns

before the SCL line is released.

Advertising