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Typical operating characteristics – Rainbow Electronics DS3903 User Manual

Page 4

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DS3903

Triple 128-Position Nonvolatile
Digital Potentiometer

4

______________________________________________________________________

Note 1:

All voltages are referenced to ground.

Note 2:

I

STBY

specified for V

CC

equal to 3.0V and 5.0V while control port logic pins are driven to the appropriate

logic levels. Appropriate logic levels specify that logic inputs are within a 0.5V of ground or V

CC

for the

corresponding inactive state. WP must be disconnected or connected high.

Note 3:

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

CC

is switched off.

Note 4:

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.

Note 5:

After this period, the first clock pulse is generated.

Note 6:

The maximum t

HD:DAT

has only to be met if the device does not stretch the low period (t

LOW

) of the

SCL signal.

Note 7:

A device must internally provide a hold time of at least 300ns for the SDA signal (referred to the V

IN MIN

of

the SCL signal) in order to bridge the undefined region of the falling edge of SCL.

Note 8:

C

B

—total capacitance of one bus line in picofarads, timing referenced to 0.9 x V

CC

and 0.1 x V

CC

.

Note 9:

EEPROM write begins after a stop condition occurs.

Note 10:

Absolute linearity is used to measure expected wiper voltage as determined by wiper position in a
voltage-divider configuration.

Note 11:

Relative linearity is used to determine the change of wiper voltage between two adjacent wiper positions
in a voltage-divider configuration.

Typical Operating Characteristics

(V

CC

= 5.0V, 10k

Ω plots apply to both pot0 and pot2, T

A

= +25°C unless otherwise noted.)

10

20

30

40

50

60

70

80

90

100

0

W-L RESISTANCE

vs. WIPER SETTING (90k

)

DS3903 toc03

WIPER SETTING

W-L RESISTANCE (k

)

125

100

75

50

25

0

W-L RESISTANCE

vs. WIPER SETTING (10k

)

DS3903 toc02

WIPER SETTING

W-L RESISTANCE (k

)

125

100

75

50

25

0

2

4

6

8

10

0

STANDBY SUPPLY CURRENT

vs. TEMPERATURE

DS3903 toc01

TEMPERATURE (

°C)

SUPPLY CURRENT (

µ

A)

50

40

-30 -20 -10

10 20

0

30

20

40

60

80

100

120

140

160

0

-40

60 70 80

V

CC

= 5V

V

CC

= 3V