pca8565-01 NXP Semiconductors, pca8565-01 Datasheet - Page 3

• Manufacturer Part Number: pca8565-01
• Description: Pca8565 Real Time Clock/calender
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8. Functional description
9397 750 10695
Product data
Fig 3. Device diode protection diagram.
7.2 Pin description
Table 3:
The PCA8565 contains sixteen 8-bit registers with an auto-incrementing address
register, an on-chip 32.768 kHz oscillator with one integrated capacitor, a frequency
divider which provides the source clock for the Real Time Clock/calender (RTC), a
programmable clock output, a timer, an alarm, a voltage-low detector and a 400 kHz
I
All 16 registers are designed as addressable 8-bit parallel registers although not all
bits are implemented. The first two registers (memory address 00H and 01H) are
used as control and/or status registers. The memory addresses 02H through 08H are
used as counters for the clock function (seconds up to years counters). Address
locations 09H through 0CH contain alarm registers which define the conditions for an
alarm. Address 0DH controls the CLKOUT output frequency. 0EH and 0FH are the
timer control and timer registers, respectively.
The seconds, minutes, hours, days, weekdays, months, years as well as the minute
alarm, hour alarm, day alarm and weekday alarm registers are all coded in BCD
format.
When one of the RTC registers is read the contents of all counters are frozen.
Therefore, faulty reading of the clock/calendar during a carry condition is prevented.
Symbol
OSCI
OSCO
INT
V
SDA
SCL
CLKOUT
V
2
C-bus interface.
SS
DD
OSCO
Pin description
OSCI
V SS
INT
Pin
1
2
3
4
5
6
7
8
Rev. 01 — 31 March 2003
1
2
3
4
PCA8565
Description
oscillator input
oscillator output
interrupt output (open-drain; active LOW)
ground
serial data I/O
serial clock input
clock output, open-drain
positive supply voltage
MCE169
8
7
6
5
V DD
CLKOUT
SCL
SDA
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
Real time clock/calender
PCA8565
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