PCF2127AT/1 NXP [NXP Semiconductors], PCF2127AT/1 Datasheet - Page 20
PCF2127AT/1
Manufacturer Part Number
PCF2127AT/1
Description
Integrated RTC, TCXO and quartz crystal
Manufacturer
NXP [NXP Semiconductors]
Datasheet
1.PCF2127AT1.pdf
(80 pages)
- Current page: 20 of 80
- Download datasheet (536Kb)
NXP Semiconductors
PCF2127A_2
Product data sheet
8.6.1.3 Battery switch-over disabled: only one power supply (V
8.6.1.4 Battery switch-over architecture
8.6.2 Battery backup supply
The direct switching mode is useful in systems where V
The direct switching mode is not recommended if the V
(e.g. V
reduced compared to the standard mode because the monitoring of V
not performed.
When the battery switch-over function is disabled:
The architecture of the battery switch-over circuit is shown in
The internal power supply (available on pin BBS) is equal to V
assured that there are decoupling capacitors on the pins V
The V
on the selected battery switch-over function mode:
Table 18.
The output pin BBS can be used as a supply for external devices with battery backup
needs, such as SRAM (see
driving capability when V
Battery switch-over function mode
standard
direct switching
disabled
Fig 6.
•
•
•
•
The power supply is applied on the V
The V
The internal power supply, available at the output pin BBS, is equal to V
The battery flag (BF) is always logic 0
BBS
DD
Battery switch-over circuit, simplified block diagram
= 3.3 V, V
voltage on the output pin BBS is equal to the internal power supply, depending
BAT
Output pin BBS
V
V
th(sw)bat
th(sw)bat
pin must be connected to ground
All information provided in this document is subject to legal disclaimers.
V
V
BAT
DD
BAT
comparators
≥ 3.0 V). In direct switching mode the power consumption is
Rev. 02 — 7 May 2010
BBS
V
V
CC
CC
Ref. 3
is driven from V
“AN10857”). For this case,
LOGIC
Conditions
V
V
V
V
V
only V
DD
DD
DD
DD
BAT
DD
logic
> V
< V
> V
< V
must be put to ground
pin
DD
DD
V
Integrated RTC, TCXO and quartz crystal
BAT
BAT
BAT
BAT
DD(int)
.
V
available,
V
BAT
DD
or V
and V
DD
DD
DD
DD
> V
switches
V
V
< V
DD(int)
DD(int)
is higher than V
and V
DD
th(sw)bat
DD
th(sw)bat
, V
Figure
Figure 7
DD
)
BAT
BAT
or V
(internal
power supply)
, and BBS.
PCF2127A
values are similar
6.
V
BAT
DD
BBS
001aag061
shows the typical
© NXP B.V. 2010. All rights reserved.
. It has to be
and V
BAT
V
V
V
V
V
V
DD
BBS
DD
BAT
DD
BAT
DD
at all times.
th(sw)bat
equals
20 of 80
is
Related parts for PCF2127AT/1
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
NXP Semiconductors designed the LPC2420/2460 microcontroller around a 16-bit/32-bitARM7TDMI-S CPU core with real-time debug interfaces that include both JTAG andembedded trace
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
NXP Semiconductors designed the LPC2458 microcontroller around a 16-bit/32-bitARM7TDMI-S CPU core with real-time debug interfaces that include both JTAG andembedded trace
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
NXP Semiconductors designed the LPC2468 microcontroller around a 16-bit/32-bitARM7TDMI-S CPU core with real-time debug interfaces that include both JTAG andembedded trace
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
NXP Semiconductors designed the LPC2470 microcontroller, powered by theARM7TDMI-S core, to be a highly integrated microcontroller for a wide range ofapplications that require advanced communications and high quality graphic displays
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
NXP Semiconductors designed the LPC2478 microcontroller, powered by theARM7TDMI-S core, to be a highly integrated microcontroller for a wide range ofapplications that require advanced communications and high quality graphic displays
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
The NXP BlueStreak LH75401/LH75411 family consists of two low-cost 16/32-bit System-on-Chip (SoC) devices
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
The NXP LPC3130/3131 combine an 180 MHz ARM926EJ-S CPU core, high-speed USB2
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
The NXP LPC3141 combine a 270 MHz ARM926EJ-S CPU core, High-speed USB 2
Manufacturer:
NXP Semiconductors
Part Number:
Description:
The NXP LPC3143 combine a 270 MHz ARM926EJ-S CPU core, High-speed USB 2
Manufacturer:
NXP Semiconductors
Part Number:
Description:
The NXP LPC3152 combines an 180 MHz ARM926EJ-S CPU core, High-speed USB 2
Manufacturer:
NXP Semiconductors
Part Number:
Description:
The NXP LPC3154 combines an 180 MHz ARM926EJ-S CPU core, High-speed USB 2
Manufacturer:
NXP Semiconductors
Part Number:
Description:
Standard level N-channel enhancement mode Field-Effect Transistor (FET) in a plastic package using NXP High-Performance Automotive (HPA) TrenchMOS technology
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
Standard level N-channel enhancement mode Field-Effect Transistor (FET) in a plastic package using NXP High-Performance Automotive (HPA) TrenchMOS technology
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
Standard level N-channel enhancement mode Field-Effect Transistor (FET) in a plastic package using NXP High-Performance Automotive (HPA) TrenchMOS technology
Manufacturer:
NXP Semiconductors
Datasheet:
Part Number:
Description:
Standard level N-channel enhancement mode Field-Effect Transistor (FET) in a plastic package using NXP High-Performance Automotive (HPA) TrenchMOS technology
Manufacturer:
NXP Semiconductors
Datasheet: