PCF2127 View Datasheet(PDF) - NXP Semiconductors.
Part Name
Description
MFG CO.
'PCF2127' PDF : 101 Pages View PDF
NXP Semiconductors
PCF2127
Accurate RTC with integrated quartz crystal for industrial applications
8.6.1.2 Direct switching mode
If VDD > VBAT: Voper(int) is at VDD potential.
If VDD < VBAT: Voper(int) is at VBAT potential.
The direct switching mode is useful in systems where VDD is always higher than VBAT.
This mode is not recommended if the VDD and VBAT values are similar (for example,
VDD = 3.3 V, VBAT 3.0 V). In direct switching mode, the power consumption is reduced
compared to the standard mode because the monitoring of VDD and Vth(sw)bat is not
performed.
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Fig 7. Battery switch-over behavior in direct switching mode with bit BIE set logic 1
(enabled)
8.6.1.3 Battery switch-over disabled: only one power supply (VDD)
When the battery switch-over function is disabled:
• The power supply is applied on the VDD pin
• The VBAT pin must be connected to ground
• Voper(int) is at VDD potential
• The battery flag (BF) is always logic 0
PCF2127
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 8 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
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