fm3204 Ramtron Corporation, fm3204 Datasheet - Page 7

• Manufacturer Part Number: fm3204
• Description: Integrated Processor Companion With Memory
• Manufacturer: Ramtron Corporation

diode and resistor charger. In 5V systems, it provides
the same convenience and also prevents the user from
exceeding the V
In the case where no battery is used, the V
should be tied according to the following conditions:
Rev. 2.4
Mar. 2008
For 3.3V systems, V
This assumes V
For 5V systems, attach a 1 µF capacitor to V
and turn the trickle charger on. The V
will charge to the internal backup voltage which
regulates itself to about 3.6V. V
be tied to 5V since the V
BAK
maximum voltage specification.
DD
does not exceed 3.75V.
BAK
BAK
should be tied to V
(max) specification
BAK
should not
BAK
BAK
BAK
pin
pin
DD
.
Although V
recommended if the companion is used. None of the
companion functions will operate below about 2.5V.
! ! ! !
the VBC bit to 0 to prevent battery charging. The
V
resistor as a safety element.
BAK
Note: systems using lithium batteries should clear
will be exceeded. A 1 µF capacitor will keep
the companion functions working for about 1.5
second.
circuitry includes an internal 1 K
BAK
may be connected to V
FM3204/16/64/256
SS
, this is not
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series