DS1834D datasheet(4/7 Pages) DALLAS

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DS1834/A/D

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OUTPUT VALID CONDITIONS

All versions of the DS1834 can maintain valid outputs as long as one input remains above 1.2 volts.

However, the RST outputs on the DS1834 use a push-pull output structure which can maintain a valid

output below 1.2 volts. To sink current below 1.2 volts a resistor can be connected from RST to GND

(see Figure 5). This arrangement will maintain a valid value on the RST outputs even if all inputs are at 0

volts. During both power-up and power-down this arrangement will draw current when RST is in the high

state. A value of about 100 k

Ω=should be adequate to maintain a valid condition.

The DS1834A requires pull-up resistors on the outputs to maintain a valid output. The value of the

resistors is not critical in most cases but must be set low enough to pull the output to a high state. A

common value used is 10 k

Ωs (see Figure 6 and Figure 7).

APPLICATION DIAGRAM:

RST

VALID TO 0 VOLTS VCC ON THE DS1834 Figure 5

APPLICATION DIAGRAM: DS1834A NMOS OUTPUTS Figure 6

Note: If outputs are pulled-up to different voltages the outputs can not be connected to form a wired

"AND".

APPLICATION DIAGRAM: DS1834A WIRED "AND" OUTPUT Figure 7

DS1834D Datasheet(PDF) 4 Page - Dallas Semiconductor