PCF2123BS/1,518 NXP Semiconductors, PCF2123BS/1,518 Datasheet - Page 13

• Manufacturer Part Number: PCF2123BS/1,518
• Description: IC RTC/CALENDAR SPI BUS 16HVQFN
• Manufacturer: NXP Semiconductors
• Type: Clock/Calendar/Alarmr

Specifications of PCF2123BS/1,518

• Time Format: HH:MM:SS (12/24 hr)
• Date Format: YY-MM-DD-dd
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 1.1 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-VQFN Exposed Pad, 16-HVQFN, 16-SQFN, 16-DHVQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Lead Free Status / Rohs Status: Compliant
• Other names: 935286382518

NXP Semiconductors
PCF2123
Product data sheet
8.4.1.1 OS flag
8.4.1 Register Seconds
8.4 Time and date function
The majority of the registers are coded in the Binary Coded Decimal (BCD) format. BCD is
used to simplify application use. An example is shown for the seconds in
Table 8.
[1]
Table 9.
The PCF2123 includes a flag (OS in register Seconds, see
the oscillator is stopped (see
by software. If the flag cannot be cleared, then the PCF2123 oscillator is not running. This
method can be used to monitor the oscillator and to determine if the supply voltage has
reduced to the point where oscillation fails.
Bit
7
6 to 4
3 to 0
Seconds value
(decimal)
00
01
02
:
09
10
:
58
59
Fig 8.
Default value.
Symbol
OS
SECONDS
OS set by failing V
Seconds - seconds register (address 02h) bit description
Seconds coded in BCD format
All information provided in this document is subject to legal disclaimers.
V
Upper-digit (ten’s place)
Bit 7
0
0
0
:
0
0
:
0
0
OSC(MIN)
Rev. 4 — 22 December 2010
V
DD
Bit 6
0
0
0
:
0
0
:
1
1
DD
Figure 8
Value
0
1
0 to 5
0 to 9
[1]
battery operation
Bit 5
0
0
0
:
0
0
:
0
0
and
Figure
Bit 4
0
0
0
:
0
1
:
1
1
Place value Description
-
-
ten’s place
unit place
9). The flag will remain set until cleared
Digit (unit place)
Bit 3
0
0
0
:
1
0
:
1
1
main supply
clock integrity is guaranteed
clock integrity is not guaranteed;
oscillator has stopped or been
interrupted
actual seconds coded in BCD
format, see
Table
SPI Real time clock/calendar
Bit 2
0
0
0
:
0
0
:
0
0
8) which is set whenever
001aai561
Table 9
PCF2123
© NXP B.V. 2010. All rights reserved.
t
Bit 1
0
0
1
:
0
0
:
0
0
Table
9.
Bit 0
0
1
0
:
1
0
:
0
1
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