DS2423

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NOTES:

1) All voltages are referenced to ground.

3) Input load is to ground.

4) An additional reset or communication sequence cannot begin until the reset high time has expired.

5) Read data setup time refers to the time the host must pull the 1-Wire bus low to read a bit. Data is

guaranteed to be valid within 1µs of this falling edge.

6) Capacitance on the data pin could be 800pF when power is first applied. If a 5kΩ resistor is used to

normal communications.

otherwise, it could mask or conceal interrupt pulses.

guarantee a Presence Pulse.

10) The counter inputs are designed for interfacing to mechanical switches and piezo sensors. If

interfacing to digital circuits, one should use an open drain driver.

11) A lower impedance pullup, e. g., for reed switches, can be achieved by connecting an external resistor

13) Each low-going edge on a counter input resets the channel’s debounce timer. The debounce time

starts as the input voltage rises beyond the trip point. In order for the next pulse to be counted the

debounce time must have expired.

the pullup resistor to recover to a high level. For a Read-Zero Time slot, it ensures that a read will

occur before the fastest 1-Wire device(s) releases the line.

15) The duration of the low pulse sent by the master should be a minimum of 1µs with a maximum value

as short as possible to allow time for the pullup resistor to recover the line to a high level before the 1-

Wire device samples in the case of a Write-One Time or before the master samples in the case of a

Read-One Time.

16) Guaranteed by design; not production tested.