CC2420RTCR Datasheet, PDF (52/94 Pages) Texas Instruments – 2.4 GHz IEEE 802.15.4 / ZigBee-ready RF Transceiver

CC2420 should then be reset before the
voltage regulator is disabled.
In applications where the internal voltage
regulator is not used, connect VREG_EN
and VREG_IN to ground. VREG_OUT shall
CC2420
be left open. Note that the battery monitor
will not work when the voltage regulator is
not used.
VREG_EN
VREG_IN
Regulator
Enable / disable
Internal
bandgap
voltage
reference
1.25 V
VREG_OUT
Figure 28. Voltage regulator, simplified schematic
30 Battery Monitor
The on-chip battery monitor enables
monitoring the unregulated voltage on the
VREG_IN pin. It gives status information
on the voltage being above or below a
programmable threshold. A simplified
schematic of the battery monitor is shown
in Figure 29.
SWRS041c
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