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Table 1. detailed pin description – Rainbow Electronics DS75LV User Manual

Page 3

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DS75LV: Digital Thermometer and Thermostat

3

of

13

Falling SCL
Low Period of SCL

t

LOW

(Note

5)

1.3

ms

High Period of SCL

t

HIGH

(Note

5)

0.6

ms

Repeated START Condition
Setup Time to Rising SCL

t

SU:STA

(Note 5)

600

ns

Data-Out Hold Time from
Falling SCL

t

HD:DAT

(Notes 5, 8)

0

0.9 ms

Data-In Setup Time to
Rising SCL

t

SU:DAT

(Note 5)

100

ns

Rise Time of SDA and SCL
(Receive)

t

R

(Notes 5, 7)

20 + 0.1C

B

300

ns

Fall Time of SDA and SCL
(Receive)

t

F

(Notes 5, 7)

20 +

0.1C

B

300 ns

Spike Suppression Filter
Time (Deglitch Filter)

t

SS

0

50 ns

STOP Setup Time to Rising
SCL

t

SU:STO

(Note 5)

600

ns

Capacitive Load for Each
Bus Line

C

B

400 pF

Input Capacitance

C

I

5 pF

Serial Interface Reset Time

t

TIMEOUT

SDA time low (Note 9)

75

325

ms

Note 1:

All voltages are referenced to ground.

Note 2:

Internal heating caused by O.S. loading will cause the DS75LV to read approximately 0.5

°C higher if O.S. is sinking the max rated

current.

Note 3:

I

DD

specified with O.S. pin open.

Note 4:

I

DD

specified with V

DD

at 3.0V and SDA, SCL = 3.0V, 0

°C to 70°C.

Note 5:

See Timing Diagram in Figure 2. All timing is referenced to 0.9 x V

DD

and 0.1 x V

DD

.

Note 6:

After this period, the first clock pulse is generated.

Note 7:

For example, if C

B

= 300pF, then t

R

[min] = t

F

[min] = 50ns.

Note 8:

The DS75LV provides an internal hold time of at least 75ns on the SDA signal to bridge the undefined region of SCL's falling edge.

Note 9:

This time-out applies only when the DS75LV is holding SDA low. Other devices can hold SDA low indefinitely and the DS75LV will
not reset.

Note
10:

The DS75LV has a maximum operating voltage of 3.7V. Contact Dallas Semiconductor for information on the availability of a 3.7V to
5.5V version of the DS75LV.

Table 1. Detailed Pin Description

PIN

SYMBOL

PIN DESCRIPTION

1 SDA

Data Input/Output. For 2-wire serial communication port. Open-drain.

2 SCL

Clock Input. 2-wire serial communication port.

3 O.S.

Thermostat Output. Open-drain.

4 GND

Ground

5 A

2

Address Input

6 A

1

Address Input

7 A

0

Address Input

8 V

DD

Supply Voltage. +1.7V to +3.7V supply pin.