Functional description

54AC164245

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DocID18093 Rev 4

1.1

Cold spare

The 54AC164245 features a cold spare input and output buffer. In high reliability

applications, cold sparing enables a redundant device to be tied to the data bus with its

injecting current from the I/Os to the power supplies. Cold sparing also allows redundant

devices to be kept unpowered so that they can be switched on only when required. Power

consumption is therefore reduced by switching off the redundant circuit. This has no impact

on the application. Cold sparing is achieved by implementing a high impedance between

structure.

1.2

Power-up

During power-up, all outputs are forced to high impedance. The high-impedance state is

signals during power-up.

1.3

Pin connections

Figure 2. Pin connections