disable the

µP and, through the address decoder

M74HC138, to ensure that the RAMS are disabled

as soon as the main supply starts to fall.

Another interesting application of the L4901A is in

µP system with shadow memories (see Figure 6).

ouput enables the execution of a routine that saves

the machine’s state in the shadow RAM (xicor x

2201 for example).

Thanks to the low consumption of the Reg. 1 a

Figure 6

Figure 7 :

Quiescent Current (reg.1) versus

Output Current

Figure 8 :

Quiescent Current (reg.1) versus

Input Voltage

L4901A

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