DS1616

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Tx (Transmit Output) - Transmit output of the asynchronous serial interface. Tx is tri-stated whenever

Rx (Receive Input) - Receive input of the asynchronous serial interface.

SCLK (3-Wire Serial Clock Input) - The SCLK pin is the serial clock input for the 3-wire synchronous

communications channel.

I/O (3-Wire Input/Output) - The I/O pin is the data Input/Output signal for the 3-wire synchronous

communications channel.

RST

communications channel.

NT

I

interrupt is present and the corresponding interrupt-enable bit is set.

INSPEC

used to signal the status of the operation and data of the DS1616.

OUTSPEC

is used to signal the status of the operation and data of the DS1616.

ST

for at least 0.5 seconds for a datalog mission to begin.

ST

AIN1, AIN2, AIN3 (Analog Inputs) - The AINx pins are the mux’ed inputs to the ADC.

X1, X2 - Connections for a standard 32.768 kHz quartz crystal, Daiwa part number DT-26S or

equivalent. For greatest accuracy, the DS1616 must be used with a crystal that has a specified load

capacitance of 6 pF. There is no need for external capacitors or resistors. Note: X1 and X2 are very high

impedance nodes. It is recommended that they and the crystal be guard-ringed with ground and that high

frequency signals be kept away from the crystal area. For more information on crystal selection and

crystal layout considerations, please consult Application Note 58, “Crystal Considerations with Dallas

Real Time Clocks.”

NC (No Connect) - These pins should be left unconnected or tied to ground.