Table Of Contents - Epson RTC-72421 A Applications Manual

RTC - 72421 / 72423
Overview ............................................................................................. 1
Block diagram ..................................................................................... 1
Terminal connections .......................................................................... 2
Terminal functions............................................................................... 3
Characteristics .................................................................................... 4
1. Absolute maximum ratings........................................................................................ 4
2. Recommended operating conditions......................................................................... 4
3. Frequency characteristics and current consumption characteristics.......................... 4
4. Electrical characteristics ( DC characteristics ) ......................................................... 4
Switching characteristics
1. When ALE is used .................................................................................................... 5
2. When ALE is fixed at V
Registers............................................................................................. 7
1. Register table............................................................................................................ 7
2. Notes ........................................................................................................................ 7
3. Functions of register bits (overview).......................................................................... 7
4. Setting the fixed-period pulse output mode and fixed-period interrupt mode............. 8
5. Resetting the fixed-period pulse output mode and fixed-period interrupt mode......... 8
Register description ............................................................................ 9
1. Timing registers ........................................................................................................ 9
2. CD register (control register D) ............................................................................... 10
3. CE register (control register E)................................................................................ 11
4. CF register (control register F) ................................................................................ 13
Using the RTC-72421/RTC-72423 .....................................................14
1. Power-on procedure (initialization) .......................................................................... 14
2. Read/write of S1 to W registers .............................................................................. 16
3. Write to 30-second ADJ bit ..................................................................................... 16
4. Using the CS
Power supply circuit example.............................................................17
Examples of connection to general-purpose microprocessor .............18
External dimensions...........................................................................19
Marking layout....................................................................................19
Reference data ..................................................................................20
Application notes................................................................................21
1. Notes on handling ................................................................................................... 21
2. Notes on packaging ................................................................................................ 21
CONTENTS
(AC characteristics)
......................................................................................... 6
DD
pin ................................................................................................... 17
1
........................................... 5