DS1775 datasheet(13/14 Pages) DALLAS

13 / 14 page

DS1775

13 of 14

AC ELECTRICAL CHARACTERISTICS:

2–WIRE INTERFACE

(–55

°C to +125°C; VDD =2.7V to 5.5V)

PARAMETER

SYMBOL CONDITION

MIN

TYP

MAX

UNITS NOTES

SCL clock frequency

fSCL

Fast Mode

Standard Mode

400

100

KHZ

Bus free time between a

STOP and START

condition

tBUF

Fast Mode

Standard Mode

1.3

4.7

Hold time (repeated)

START condition

tHD:STA

Fast Mode

Standard Mode

0.6

4.0

LOW period of SCL

tLOW

Fast Mode

Standard Mode

1.3

4.7

HIGH period of SCL

tHIGH

Fast Mode

Standard Mode

0.6

4.0

Set-up time for a

repeated START

tSU:STA

Fast Mode

Standard Mode

0.6

4.7

Data hold time

tHD:DAT

Fast Mode

Standard Mode

0.9

Data set-up time

tSU:DAT

Fast Mode

Standard Mode

100

250

Rise time of both SDA and

SCL signals

Fast Mode

Standard Mode

20+

0.1CB

300

1000

Fall time of both SDA and

SCL signals

Fast Mode

Standard Mode

20+

0.1CB

300

Set-up time for STOP

tSU:STO

Fast Mode

Standard Mode

0.6

4.0

Capacitive load for each bus

line

400

Input Capacitance

NOTES:

1. All voltages are referenced to ground.

2. I/O pins of fast mode devices must not obstruct the SDA and SCL lines if VDD is switched off.

3. IDD specified with O.S. pin open.

4. IDD specified with VDD at 5.0V and SDA, SCL = 5.0V, 0

°C to +70°C.

5. After this period, the first clock pulse is generated.

6. The maximum tHD:DAT has only to be met if the device does not stretch the LOW period (tLOW ) of the

SCL signal.

7. A fast mode device can be used in a standard mode system, but the requirement tSU:DAT

³ 250 ns must

then be met. This will automatically be 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 tR MAX +tSU:DAT = 1000+250 = 1250 ns before the SCL line is released.

8. Cb – total capacitance of one bus line in pF.

9. Internal heating caused by O.S. loading will cause the DS1775 to read approximately 0.5ºC higher if

O.S. is sinking the max rated current.

10. Contact the factory in Dallas, (972) 371-4448, for operation requiring temperature readings greater

than 120°C.

DS1775 Datasheet(PDF) 13 Page - Dallas Semiconductor

DS1775 Datasheet(HTML) 13 Page - Dallas Semiconductor

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Datasheet Download

Link URL