PCF2129AT/2,518 NXP Semiconductors, PCF2129AT/2,518 Datasheet - Page 38

• Manufacturer Part Number: PCF2129AT/2,518
• Description: Real Time Clock
• Manufacturer: NXP Semiconductors
• Series: PCF2129r

Specifications of PCF2129AT/2,518

• Rohs: yes
• Function: Clock, Calendar, Alarm, Watchdog, Timestamp
• Rtc Bus Interface: I2C, SPI
• Date Format: Binary
• Time Format: Binary
• Supply Voltage - Max: 4.2 V
• Supply Voltage - Min: 1.2 V
• Maximum Operating Temperature: + 60 C
• Minimum Operating Temperature: - 15 C
• Mounting Style: SMD/SMT
• Package / Case: SOP-20
• Battery Backup Switching: Yes
• Factory Pack Quantity: 2000

NXP Semiconductors
PCF2129AT
Product data sheet
Fig 19. Interrupt block diagram
When SI, MI, WD_CD, AIE, TSIE, BIE, BLIE are all disabled, INT will remain high-impedance (output HIGH).
SECONDS COUNTER
MINUTES COUNTER
8.12 Interrupt output, INT
watchdog counter
PCF2129AT has an interrupt output pin INT which is open-drain, active LOW (requiring a
pull-up resistor if used). Interrupts may be sourced from different places:
circuit: clear BF
•
•
•
•
•
•
WATCHDOG
from interface:
from interface:
from interface:
set timestamp
from interface:
WD_CD = 1
COUNTER
low detection
MCU loading
low flag, BLF
from battery
second or minute timer
watchdog timer
alarm
timestamp
battery switch-over
battery low detection
set battery
set battery
flag, TSFx
clear MSF
clear TSF
set alarm
clear AF
clear BF
flag, AF
flag, BF
MI
SI
All information provided in this document is subject to legal disclaimers.
SET
SET
SET
SET
SET
TSFx: TIMESTAMP
BLF: BATTERY
SET
BF: BATTERY
SECOND FLAG
TIMER FLAG
WATCHDOG
AF: ALARM
LOW FLAG
WDTF:
CLEAR
CLEAR
CLEAR
CLEAR
CLEAR
MINUTE
FLAG
FLAG
FLAG
Rev. 5 — 12 February 2013
CLEAR
MSF:
TRIGGER
GENERATOR 1
to interface:
read MSF
to interface:
read WD_CD
to interface:
read AF
to interface:
read TSFx
to interface:
read BF
to interface:
read BLF
PULSE
CLEAR
Integrated RTC, TCXO and quartz crystal
0
1
TI_TP
WD_CD = 0
SI/MI
TSIE
BLIE
AIE
BIE
PCF2129AT
001aaj399
© NXP B.V. 2013. All rights reserved.
INT pin
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