DP8573AV National Semiconductor, DP8573AV Datasheet - Page 13

• Manufacturer Part Number: DP8573AV
• Description: Clock IC
• Manufacturer: National Semiconductor

Specifications of DP8573AV

• Date Format: BCD
• Clock Format: 12 Or 24 Hr
• Clock Ic Type: RTC
• Digital Ic Case Style: LCC
• No. Of Pins: 28
• Peak Reflow Compatible (260 C): No
• Supply Voltage Max: 5.5V
• Leaded Process Compatible: No
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Main Status Register PS
Periodic Flag Register PS
Time Save Control Register PS
Real Time Mode Register PS
Output Mode Register PS
Interrupt Control Register 0 PS
Interrupt Control Register 1 PS
Control and Status Register Address Bit Map
Time Save
Power Fail
Application Hints
Suggested Initialization Procedure for DP8573A in Bat-
tery Backed Applications that use the V
1
2
3
Interrupt
MFO as
Enable
Enable
Crystal
Mode
R W
RAM
R W
RAM
RAM
Test
Enter the test mode by writing a 1 to bit D7 in the Period-
ic Flag Register
Write zero to the RAM TEST mode Register located in
page 0 address HEX 1F
Leave the test mode by writing a 0 to bit D7 in the Peri-
odic Flag Register Steps 1 2 3 guarantee that if the
test mode had been entered during power on (due to
random pulses from the system) all test mode condi-
tions are cleared Most important is that the OSC Fail
Disable bit is cleared Refer to AN-589 for more informa-
tion on test mode operation
D7
Single Supply
Osc Fail
Register
Interrupt
Enable
Select
R W
Alarm
R W
RAM
RAM
RAM
N A
D6
4
e
e
e
X RS
0
0
e
Interrupt
Interrupt
Enable
Enable
e
0
e
e
DOW
RAM
RAM
RAM
RAM
R W
1 ms
1 ms
Flag
D5
R
0
e
0
0
5
RS
RS
X ADDRESS
RS
e
e
RS
RS
RS
BB
Interrupt EN
on Back-Up
0
1
e
Interrupt
Interrupt
Enable
Enable
Month
10 ms
10 ms
Pin
e
RAM
RAM
1
RAM
e
e
R W
Flag
D4
R
0 Address
5
1
1
Address
Address
e
Address
00H
Address
Address
Start Stop
Interrupt
Interrupt
Interrupt
100 ms
100 ms
Enable
Enable
R W
Alarm
Clock
e
e
e
RAM
RAM
DOM
Flag
D3
R
13
02H
03H
5
04H
e
1
01H
e
e
4
4 1 Write a 1 to bit D3 in the Real Time Mode Register (try
03H
04H
Enter a software loop that does the following
Set a 3 second(approx) software counter The crystal
oscillator may take 1 second to start
to start the clock) Under normal operation this bit can
be set only if the oscillator is running During the soft-
ware loop RAM real time counters output configura-
tion interrupt control and timer functions may be initial-
ized
12 24 Hr
Seconds
Seconds
Interrupt
Interrupt
Interrupt
Periodic
Enable
Enable
R W
Mode
Hours
RAM
RAM
Flag
D2
R
5
1
10 Second
10 Second
Power Fail
Leap Year
Interrupt
Interrupt
Interrupt
Enable
Minute
Enable
RAM
RAM
MSB
Flag
D1
R
R
2
5
Leap Year
Interrupt
Interrupt
Interrupt
Second
Minute
Minute
Enable
Enable
Status
RAM
RAM
Flag
LSB
D0
R
R
3
5
1 Reset by
2 Set reset by
3 Reset when
4 Read Osc fail
5 Reset by
All Bits R W
All Bits R W
All Bits R W
All Bits R W
All Bits R W
writing
1 to bit
voltage at
PFAIL pin
all pending
interrupts
are removed
Write 0 Batt-
Backed Mode
Write 1 Single
Supply Mode
positive edge
of read