DS1315

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NONVOLATILE CONTROLLER OPERATION

The operation of the nonvolatile controller circuits within the Time Chip is determined by the level of the

and performs the circuit functions required to make CMOS RAM and the timekeeping function

SRAM. The DS1315 also performs redundant battery control for high reliability. On power-fail, the

system, the unused battery input should be connected to ground.

The DS1315 safeguards the Time Chip and RAM data by power-fail detection and write protection.

any data transfer in progress without changing any of the Time Chip registers and prevents future access

read-only device that retains data in the absence of power, battery backup and write protection is not

Chip does retain the same internal nonvolatility and write protection as described in the RAM mode. A

typical ROM/Time Chip interface is illustrated in Figure 4.

DS1315 TO RAM/TIME CHIP INTERFACE Figure 3