ACE5372

Low Power Real-Time Clock (RTC)

VER 1.3

3

Bypass Capacitance

OSCIN and OSCOUT

These pins configure an oscillator circuit by connecting a crystal oscillator between the OSCIN-OSCOUT

pins.

The diagram beside shows the connection method of such crystal oscillator circuit. It’s

recommended to choo

se the right crystal oscillator parameter referring to the supplier’s suggestion, since

it does determine the start-up reliability and oscillation stability provided by external devices. The

influence of the distributing capacitance should be considered when choosing capacitance capacity in an

oscillator circuit. To minimize output distortion, both crystal oscillator and capacitance should be installed

as close to ACE5372 pin as possible.

ACE5372

Crystal Oscillator

Connection with External

Capacitance

SCL and SDA

SCL and SDA are Serial Clock Line and Serial Data Line, relatively. SCL is used to input shift clock

pulses to synchronize data input/output to and from the SDA pin with this clock. SDA inputs and outputs

written or read data in synchronization with shift clock pulses from the SCL pin. Depend on different level

of current, separate pull-up resistance can be added to SCL and SDA on exterior circuit board.

INTRA and INTRB

INTRA and INTRB are two interrupt output ports and are both open drain outputs. When using ACE5372

a pull-up resistance must be connected with pins of INTRA and INTRB. INTRA could output periodic

interrupt pulses and alarm interrupt (ALARM-A, ALARM-B); INTRB could output 32.768KHz clock pulses

(when 32.768KHz crystal is used), periodic interrupt pulses, alarm interrupt (ALARM-B). When power is

activated from 0V, it could output 32.768kHz clock pulses (when 32.768KHz crystal is used).

Functional Descriptions

Allocation of Internal Addresses

Internal

Address

Contents

Function

0H

Second Counter

Counting and storing seconds in BCD codes

1H

Minute Counter

Counting and storing minutes in BCD codes

2H

Hour Counter

Counting and storing hours in BCD codes

3H

Day of the Week Counter

Counting and storing days of the week in BCD codes

4H

Day Counter

Counting and storing days in BCD codes

5H

Month Counter

Counting and storing months in BCD codes

6H

Year Counter

Counting and storing years in BCD codes