Contents

Features.............................................................. 1
Applications......................................................... 1
Block Diagram..................................................... 1
Pin Assignment ................................................... 1
Pin Function ........................................................ 2
Command Configuration ..................................... 2
Data Configuration .............................................. 3
Ordering Information ........................................... 3
Absolute Maximum Ratings................................. 3
Recommended Operating Conditions ................. 4
DC Characteristics .............................................. 4
Oscillation Characteristics ................................... 5
AC Characteristics 1 (S-3510ANFJX,
S-3510AEFJX, RL1=30 k

, CL1=50 pF) ............ 6

AC Characteristics 2 (S-3510ACFJX,
S-3510ADFJX, CL1=50 pF) ................................ 6
AC Characteristics 3 (S-3510ACFJX,
S-3510ADFJX, CL1=50 pF) ................................ 6
Timing Charts...................................................... 7
Operation ............................................................ 8
Application Circuit Examples ............................... 13
Dimensions ......................................................... 14
Taping Specifications .......................................... 15
Precautions ......................................................... 16
Characteristics .................................................... 17

Frequently Asked Questions................................ 20

Seiko Instruments Inc.

The S-3510 is a series of CMOS real-time clock ICs that inputs/ outputs
serial clock or calendar data into/from the CPU.

Features

Applications

Block Diagram

Pin Assignment

REAL-TIME CLOCK

S-3510 Series

Operating power supply:

1.7 V to 5.5 V

Low current consumption: 2.0

A typ. at 3.0 V

(S-3510AFFJA : 2.0

A typ.

at 3.0 V)

BCD output of second, minute, hour, day, date, month and

year

Easy serial interface to CPU with 3 lines (SIO, SCK, and CS)

Built-in automatic calendar

Built-in voltage detector

Built-in constant voltage circuit

Built-in oscillation circuit (Cg and Cd are built in)

Video cameras

FAXes

Cellular phones

Printers

SIO

Sec.

Min.

Hr.

Day

Date

Mon.

Year

Counter

Sec.

Min.

Hr.

Day

Date

Mon.

Year

Shift Register

Status Register

Serial Interface

Controller

SCK

OSC

&
Divider

OUT

Voltage

Detector

Figure 1

OUT

SIO

SCK

Figure 2

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

Pin Function

Command Configuration

Table 2

Command

Code

Note

READ 1(Data Read)

1 1 1 0

Output from the year data

READ 2(Data Read)

1 1 1 1

Output from the day data

WRITE 1(Data Write)

1 0 0 1

Input from the year data

WRITE 2(Data Write)

1 0 0 0

Input from the day data

STATUS

WRITE

1 0 1 1 D3 D2 D1 D0

Status write

RESET

1 0 1 0 1 0 1 0

Initialization

TEST START

1 1 0 1 0 1 0 1

Test mode start

TEST END

1 1 0 1 1 0 1 0

Test mode end

No.

Name

Function

OUT

Standard signal output (Nch open-drain output or CMOS output)

OUT

Connects to the X

ftal resonator (f=32768 Hz)

[Cg and Cd are built in]

Power supply (GND)

Chip select input (Built-in pull-down resistance)

The SIO pin is capable of inputting/outputting data.

The SCK pin is capable of accepting the input.

The SIO pin is at Hi-Z.

The SCK pin is not capable of accepting the input.

SCK

Clock input:

Inputs and outputs data from the SIO pin in synchronization with the clock. The

clock cannot be accepted when the CS pin is

SIO

Serial data input/output:

When the CS is

the SIO pin is at

Hi-Z.

When the CS pin changes from

it serves as the input pin. The SIO pin is assigned to the input or output pin

according to the next command data. The type of output is either Nch open-drain

or CMOS depending upon the model of the IC you use.

Positive power supply

Table 1

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

Data Configuration

The S-3510 series is provided with a timer data BCD (Binary Coded Decimal) display

(

*) device and an

automatic calendar

A set of flags are configured as follows:

Ordering Information

Table 3

Model No.

SIO output

OUT

output

TPout output

form

Oscillation circuit capacity

Note

S-3510ANFJX

Nch open-

drain

Selection of 1H

/32768H

by command

Nch open-drain

Internal Cg,Cd

Under mass

production

S-3510ACFJX

CMOS

Selection of 1H

/32768H

by command

Nch open-drain

Internal Cg,Cd

Under mass

production

S-3510ADFJA

CMOS

32768H

Nch open-drain

External Cg, Internal Cd

Under development

S-3510AEFJA

Nch open-

drain

32768H

Nch open-drain

Internal Cg, Cd

Under development

S-3510AFFJA

CMOS

32768H

CMOS

External Cg, Internal Cd

Under mass

production

* X differs depending on the package type : A : A type, (blank) : B type

Absolute Maximum Ratings

Table 4

Parameter

Symbol

Conditions

Ratings

Unit

Power supply voltage

-0.3 to +7.0

Input Voltage

IN1

SCK, CS, SIO

-0.3 to +7.0

IN2

SIO (CMOS output)

-0.3 to V

+0.3

Output voltage

OUT

, SIO

-0.3 to +7.0

Operating temperature

Topr

=3.0 V

-30 to +80

Storage temperature

Tstg

-55 to +125

12/24

POW

BLD

AM/PM

TPF FRE

TPEN

Year data (0 to 99)

Month data (1 to 12)

Date data (1 to 31)

Status and day data (1 to 7)

Hour data (0 to 23 or 0 to 11) and flags

Minute data (0 to 59) and flags

Second data (0 to 59) and flags

( * )Notes AM /PM Flag:

When writing in 12-hour display mode, always input 0 for AM and 1 for PM. In 24-hour display

mode, it is unnecessary as both 1 and 0 are ignorged. However, when reading the time in either

display mode0 is read as AM 1 as PM.

BLD Flag:

When a decrease in the voltage is detected, it is set to 1. This is valid during reading; and is

invalid during writing.

POW Flag:

1 is set at the power ON, and cleared through the RESET command. This flag is ingored during

writing.

TEST Flag:

When the test mode is set, it is set to 1. When the bit is 1, ALWAYS USE the TEST END or

RESET command to set to 0. This bit is valid for reading and ignored during writing.

TEST

Ta=25

C V

=0 V

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

Recommended Operating Conditions

Table 5

Parameter

Symbol

Min.

Typ.

Max.

Unit

Power supply voltage

1.7

3.0

5.5

Operating temperature

Topr

-20

+70

DC Characteristics

Parameter

Symb.

Conditions

Standard

Unit

Note

Min.

Typ.

Max.

Operating voltage

range

Ta=-20

C to +70

1.7

3.0

5.5

1.2

3.5

2, 15

2.0

3.5

2, 16

S-3510ANFJX/ AEFJA

3,11

S-3510ACFJX/ ADFJA/AFFJA

3,12

IHL1

=5.5 V

-0.5

0.5

Input leak current

IHL2

-0.5

0.5

ILL

=0 V

-0.5

0.5

IH2

=5.5 V

IH3

=0.4 V

100

300

0.8

0.2

OL1

=0.4 V

200

OL2

=0.4 V

500

OH1

=2.6 V

-200

OH2

=2.6 V

-500

1.8

2.0

2.2

Ta=-20

C to +70

1.72

2.3

BLD current

consumption

BLD

Ta=-20

C to +70

0.3

1.0

Unless otherwise specified,

Ta=25

C,V

=3.0 V, X

tal resonator: Seiko Instruments Inc.,

DS-VT-200 (R

=30 k

, C

=6 pF, 32768 Hz)

Note 10 Applied to the SIO of the S-

3510ACFJX, the S-3510ADFJA, the

S-3510AFFJA

Note 11

Communications when SCK=100

kHz

Note 12 Communications when SCK=500

kHz

Note 13 The value of the current which flows

through the voltage detector when it

starts to function

Note 14

Applied to the TPout of the S-

3510AFFJA

Note 15

Applied to the products except the S-

3510AFFJA

Note 16

Applied to the S-3510FFJA

Note 5

Applied to the SIO, SCK of the S-

3510ACFJX, the S-3510ADFJA,

the S-3510AFFJA

Note 6

Applied to the SIO, SCK, CS

Note 7

Applied to the CS

Note 8

Applied to the TP

OUT

Note 9

Applied to the SIO

Note 1

Communications when

SCK=100 kHz

Note 2

No output load,

communication inhibit

Note 3

The current which flows

through the CS is not

included, no output load

Note 4

Applied to the SIO, SCK of

the S-3510ANFJX, the S-

3510AEFJA

Table 6

Power current

consumption

DD2

Voltage detection

voltage

DET

Input voltage

Input current

DD1

CS=0 V

Output current

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

Oscillation Characteristics

Table 7

Ta=25

C, V

=3.0 V, X

ftal resonator: Seiko Instruments Inc., DS-VT-200 (R

=30 k

, C

*=6 pF, 32768 Hz)

Standard

Min.

Typ.

Max.

Oscillation start

voltage

STA

Within 10 sec

1.7

5.5

Oscillation start

time

STA

3.0

Frequency

deviation between

ICs

-10

+10

ppm

Frequency voltage

deviation

=1.7 V to 5.5 V

-3

ppm

Input capacitance

IN1

Applied to X

Input capacitance

IN2

Applied to X

Output

capacitance

OUT

Applied to X

OUT

* The load capacitance (C

) changes depending upon the capacitance of the PCB mounted onto the IC.

ADJUST the load capacitance.

*1 Applied to S-3510ANFJX, S-3510ACFJX, S-3510AEFJA (Internal) .
*2 Applied to S-3510ADFJA, S-3510AFFJA (External) .
*3 Applied to S-3510ANFJX, S-3510ACFJX, S-3510AEFJA, S-3510ADFJA, S-3510AFFJA (Internal) .

Parameter

Conditions

Symbol

Note

Unit

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

AC Characteristics 1

(S-3510ANFJX, S-3510AEFJA, R

=30 k

, C

=50 pF)

Table 8

Conditions

=1.7 V to 5.5 V, Ta=-20

C to 70

C, Interface voltage Vcc=5.0 V

Input: V

=0.8

, V

=0.2

, Output: V

=0.8

, V

=0.2

Parameter

Symbol

Min.

Typ.

Max.

Unit

Clock pulse width

SCK

250000

Setup time prior to the rising of the CS

Hold time after the rising of the CS

CSH

Input data setup time

ISU

Input data hold time

IHO

Output data determination time

ACC

3.5

Setup time prior to the falling of the CS

CSS

Hold time after the falling of the CS

Input rising/falling time

0.1

AC Characteristics 2

(S-3510ACFJX, S-3510ADFJA, S-3510AFFJA, C

=50 pF)

Table 9

Conditions : V

=5.0

0.5 V, Ta=-20

C to 70

Input: V

=0.8

, V

=0.2

, Output: V

=0.8

, V

=0.2

Parameter

Symbol

Min.

Typ.

Max.

Unit

Clock pulse width

SCK

0.5

250000

Setup time prior to the rising of the CS

0.1

Hold time after the rising of the CS

CSH

0.1

Input data setup time

ISU

0.1

Input data hold time

IHO

0.1

Output data determination time

ACC

0.3

Setup time prior to the falling of the CS

CSS

0.1

Hold time after the falling of the CS

0.1

Input rising/falling time

0.05

AC Characteristics 3

(S-3510ACFJX, S-3510ADFJA, S-3510AFFJA, C

=50 pF)

Table 10

Conditions : V

=3.0

0.6 V, Ta=-20

C to 70

Input: V

=0.8

, V

=0.2

, Output: V

=0.8

, V

=0.2

Parameter

Symbol

Min.

Typ.

Max.

Unit

Clock pulse width

SCK

1.0

250000

Setup time prior to the rising of the CS

0.2

Hold time after the rising of the CS

CSH

0.2

Input data setup time

ISU

0.2

Input data hold time

IHO

0.2

Output data determination time

ACC

0.6

Setup time prior to the falling of the CS

CSS

0.2

Hold time after the falling of the CS

0.2

Input rising/falling time

0.05

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

Operation

(1) Initialization

When the power is switched on, the POW flag is assigned via the power-on detector. ALWAYS TURN the CS to

Regardless of the logic of the POW flag, initialization must be executed. Therefore, ALWAYS SEND the RESET command

(10101010) from the CPU.

This allows the divider, counter and status register of the S-3510 series to be reset. Namely, the second, minute, hour,

day, date, month, and year (00 sec., 00 min., 00 hr., Sunday (1), January (01), 00 year) are set, and the counter starts to

operate upon the falling edge of the CS.

(2) Write to the Status Register

The S-3510 series is provided with a 4-bit status register. To write the data in the register, send the STATUS WRITE

command (1011D3D2D1D0). This data is retrieved in synchronization with the falling edge of the CS.

Upon initialization, (D3, D2, D1, D0) is set to (1, 0, 1, 0).

In other words,

In the S-3510ANFJX, the S-3510ACFJA, 1 Hz is output from TP

OUT

, and the status is set to the 24-hour display

mode.

In the S-3510AEFJX, the S-3510ADFJA, the S-3510AFFJA, 32768 Hz is output from TP

OUT

, and the status is set to

the 24-hour display mode.

When initialization is not executed, the data of the status register is not specified. ALWAYS execute initialization when

switching on the power.

SIO

SCK

Input

Reset

Figure 6

Free bit:

Stores the information according to a user-specified memory
bit. It does not affect the function of the timer. Reset to

during initialization.

OUT

output frequency-select bit (*)

In the S-3510ANFJA, the S-3510ACFJX

0: 32768 Hz

1: 1 Hz

In the S-3510AEFJA, the S-3510ADFJA, the S-3510AFFJA

0, 1: 32768 Hz (It can be used as Free bit)

OUT

enable bit

In the S-3510ANFJX, the S-3510ACFJX

0: Output

1: High impedance

In the S-3510AEFJA, the S-3510ADFJA, the S-3510AFFJA

0, 1: Output (It can be used as Free bit)

12/24-hour display change bit 0: 12-hour display

1: 24-hour display

(*)

PLEASE NOTE that when the frequency-select bit is rewritten during operation, the first pulse generated immediately after the CS is turned to

cannot be output at the correct frequency.

SIO

SCK

Figure 7

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

(3) Data Read

The time data can be read by sending the READ command after the CS goes "H." The data is output in order of the LSB of

the day or year.

After the READ command is interpreted, the time data is transmitted from the counter to the shift register. In

synchronization with the falling edge of the 9th clock, the SIO status changes from input to output, and the LSB of the timer

register is output. After then, in synchronization with the falling edge of the clock, the time data is output from the shift

If the power supply voltage detector activates, the MSB (BLD bit) is set to"1," which allows the power supply voltage to be

monitored. For more details, refer to the "(6) Voltage Detector".

(4) Data Write

Sending the WRITE command after the CS changes from "L" to"H" halts the update operation and resets the frequency

divider. This allows the time data to be written. The data is input in order of the LSB of the day or year. The time data

transmitted from the SIO is written in the shift register in synchronization with the rising edge of the clock. After transmission of

the minute data has been completed, the currently-stored data is transmitted to the counter during the period of the transmission

of the second data, and the month-end correction is executed. The second data is transmitted from the shift register to the

second counter in synchronization with the point where the CS changes from "H" to"L." Accordingly, the second data error

processing is not performed. Turning the CS to "L" allows the divider to run and update operation to start. One second after,

the carry-up signal is transmitted to the second counter. If non-existent data is written in the second counter, the second

counter is set to "00," and the carry-up signal is transmitted to the minute counter.

WWW
0 1 2

m
6

m
5

12
24

m
6

BLD

T
P
E
N

T
P
F

F
R
E

S S S S S S
1 2 3 4 5 6

S
0

P
O
C

Y
7

Y
6

Y
5

Y
4

Y
3

Y
2

Y
1

Y
0

M
0

Output Mode Change

READ1 mode

SCK

READ 2 mode

S S S S S S
1 2 3 4 5 6

S
0

P
O
C

BLD

H
0

m
5

SCK

SIO

T
e
s
t

Figure 8

Output Mode Change

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

WWW
0 1 2 X

m
6 X

m
5

S S S S S S
1 2 3 4 5 6

S
0

Y
7

Y
6

Y
5

Y
4

Y
3

Y
2

Y
1

Y
0

M
0

WRITE 1 mode

SCK

SIO

H H H
0 1 2

X X X

m
6

WRITE 2 mode

S S S S S S
1 2 3 4 5 6

S
0

m
5

SCK

SIO

[Notes]

When the CS is turned to "L,"correct data cannot be written.

NEVER TURN THE CS TO "L" BEFORE WRITE IS COMPLETED. Refer to the timing chart shown below:

Dividing steps are reset at "H."

All bits of the minute, hour and day (date, month, and year) counter are zero cleared at
"H."

With respect to the bit where the data written in the minute, hour and day (date, month,
and year) counter is 1, 1 is set at "H."

Invalid data processing is performed at "H."

Month-end processing is performed at "H."

The second data is written at "H."

S
0

m
6 X

X X X X

Y
1

Y
0

S S S S S
2 3 4 5 6

S
1

SCK

SIO

Figure 9

Figure 10

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

(5)

Month-End Correction

When the time data is written in the counter, its validity is checked and either invalid data or month-end processing is

performed.

[Data Processing]

Table 11

Normal data

Error data

Result

Day data

1 to 7

Date data

01 to 31

00, 32 to 39, XA to XF

Month data

01 to 12

00, 13 to 19, XA to XF

Year data

00 to 99

XA to XF, AX to FX

Second data (*)

00 to 59

60 to 79, XA to XF

Minute data

00 to 59

60 to 79, XA to XF

Hour data (24-hour)

(**)

(12-hour)

0 to 23

0 to 11

24 to 29, 3X, XA to XF

12 to 19, XA to XF

(*)

Invalid data processing for the second data is performed through the carry pulse 1 second after
the completion of writing. The carry pulse is sent to the minute counter.

(**)

Write 0 or 1 into the AM/PM flag using the 12-hour display.
For the 24-hour display, 0 or 1 is neglected when writing into the AM/PM flag. When reading,
however, 0 is read during 0 to 11 o

clock, and 1 is read during 12 to 23 o

clock.

[Month-End Processing]

Non-existent days at the end of the month are automatically processed as the 1st day of the following month. For example,

April 31 is automatically set to May 1. Leap years are allso adjusted.

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

(6) Voltage Detector

The S-3510 series incorporates a voltage detector that performs sampling once a second for 62.5 msec.

When the supply voltage goes below the detection voltage, the BLD latch-up circuit latches

and stops sampling.

[IMPORTANT]

The BLD flag can read 1 when the supply voltage increases and the first read is executed. After that, however, sampling is
permitted. Therefore, when the next read is performed after sampling of the detector, the BLD flag is reset. Refer to the
timing charts shown below:

When the CS is turned to "H," the output of the latch-up circuit is transmitted to the shift register only when the subsequent
command is the READ command.
Reading the BLD bit allows the decrease in the voltage to be monitored.

If the CS is turned to "L" after completing the read, sampling restarts. That is, once a decrease in the voltage is detected,

detection is not performed and the status is kept "H" as long as an initialization is not performed or a READ command is not

sent.

Sampling

pulse

Carry pulse

(0)

1 sec

Halt

(1)

(1) (1)

(0)

Latch circuit output

BLD flag

[Timing of Sampling Pulse]

1Hz

DET

Sampling

pulse

0.5 sec

7.8 msec

Carry-up timing

Latch timing

62.5 msec

31.25 msec

62.5 msec

Latch pulse

Figure 11

Figure 12

Halt

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

Application Circuit Examples

(1) S-3510ANFJX, S-3510AEFJX (Nch open-drain output)

(2) S-3510ACFJX, S-3510ADFJX (CMOS output)

Vcc

OUT

S-3510ANFJX/AEFJA

SCK

SIO

OUT

Vss

Vcc

External CPU

Figure 13

S-3510ACFJX/ADFJA

In the case of (2) or (3), the voltage of more than V

cannot be applied to the SIO,CS,SCK. For

communication purpose, switch the system power supply (V

) on, and turn the CS to "H" after the

system power supply stabilizes. ALWAYS TURN THE CS TO "L" AND SWITCH THE SYSTEM

POWER SUPPLY OFF.

OUT

SCK

SIO

OUT

Vss

Vcc

External CPU

Power
supply

change

circuit

Vcc

Figure 14

When V

, the SCK and CS terminals can be directly connected to the CPU because there is no flow of current

from the CPU.

S-3510AFFJA

OUT

SCK

SIO

OUT

Vss

Vcc

External CPU

Figure 15

(3) S-3510AFFJ (SIO:CMOS output, TPout:CMOS output)

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

Dimensions

There are two types of packages : A or B.

1.27

0.10 min.

0.40

0.05

1.50

0.05

1.75max.

3.9

4.90 (4.95 max.)

6.00

0.20

0.05

0.60

0.20

Marking

A type

S-3510ANFJA
S-3510ACFJA
S-3510ADFJA
S-3510AEFJA
S-3510AFFJA

1.27

0.10 min.

0.42

0.09

1.47

0.05

1.75max.

3.9

4.90 (5.00 max.)

6.00

0.20

0.22

0.03

0.84

Figure 18

Marking

B type

S-3510ANFJ
S-3510ACFJ

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

(3) Reel Dimensions (2,000 pcs / 1 reel)

Precautions

(1) The oscillation which uses a quartz crystal resonator is sensitive to external noise which may have an effect on the

accuracy of the watch. MAKE SURE to design your oscillation circuit with this in mind.

A) Configure the quartz crystal resonator as close to the IC as possible.

B) Take measures for sufficient insulation between pins X

and X

OUT

C) DO NOT design a circuit where signal lines or the power lines pass close to the oscillation circuit.

(2) When using other resonators, not specified herein or other than the DS- VT-200, ALWAYS check the accuracy and

stability of the oscillation by changing conditions such as the power supply voltage and temperature on the actual

PCB you use.

(3) The load capacitance (C

) of the quartz crystal resonator visibly changes depending upon the capacitance of the

PCB mounted onto the IC. Adjust the load capacitance.

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

Characteristics

(V)

DD1

(

Ta=25

1.1 I

DD1

- V

(The products except

the S-3510AFFJA)

(V)

DD2

(

SCK=100 kHz
Interface 5 V
Ta=25

2.1 I

DD2

- V

(S-3510ANFJ

, S-3510AEFJA)

-50

100

DD2

(

SCK=100 kHz
Interface 5 V

2.2 I

DD2

- Ta

(S-3510ANFJ

, S-3510AEFJ

)

(

=5.0 V

=3.0 V

-50

100

DD2

(

SCK=500 kHz

2.3 I

DD2

- Ta

(S-3510ACFJ

, S-3510ADFJA,

S-3510FFJA)

(

=5.0 V

=3.0 V

400

1,000

120

DD2

(

2.4 I

DD2

- f

SCK

(S-3510ACFJ

, S-3510ADFJA,

S-3510AFFJA)

SCK

( kHz)

=5.0 V

=3.0 V

1.2 I

DD1

- Ta

(

DD1

(

-50

100

=5.0 V

=5.5 V

=3.0 V

=1.7 V

(V)

DD1

(

Ta=25

(S-3510AFFJA)

REAL-TIME CLOCK
S-3510 Series

Seiko Instruments Inc.

0.2

0.4

0.6

(V)

BLD

(

Ta=25

3.1 I

BLD

- V

(

BLD

(

3.2 I

BLD

- Ta

-50

100

1.6

1.8

2.2

DET

(V)

3.3 BLD detection voltage temperature

characteristics

OL1

(mA)

4.1 TP

out

pin output transistor

characteristics

out

pin voltage (V)

=5.0 V

=3.0 V

OL2

(mA)

4.2 SIO pin output transistor

characteristics

=5.0 V

=3.0 V

-8

-6

-4

-2

OH2

(mA)

4.3 SIO pin output transistor

characteristics

=5.0 V

=3.0 V

-50

100

0.2

0.4

0.6

=5.0 V

=5.5 V

=3.0 V

=1.7 V

(

SIO pin voltage (V)

Ta=25

SIO pin voltage (V)

Ta=25

Nch

Pch

REAL-TIME CLOCK

S-3510 Series

Seiko Instruments Inc.

f( V

) - f(3 V)

f(3 V)

0.4

CS pin voltage (V)

(mA)

Ta=25

5.1 CS pin input current characteristics

(V)

(ppm)

6.1 Oscillation frequency voltage deviation

6.2 Oscillation frequency temperature deviation

(V)

7.1 Power-on detector characteristics

-4

-2

(

=5.0 V

=3.0 V

Ta=25

(ppm)

f (Ta) - f(25

f (25

(ppm)

= Condition where power-on is detected:

10ms.

= Condition where the data is retained and

the IC functions normally when the
power supply voltage falls:
t

1ms.

= Condition where the data is retained and

the IC functions normally when the
power supply voltage rises:
t

1ms.

5.5

1.7

Ta= - 20

C to+70

-50

-120

-80

-40

=3.0 V

Collection of Product FAQs

Author: Shirai Masaaki

Date: 99/04/16 (Friday) 18:20 (modified: 99/04/16(Friday))

Public (Printing O.K.)

Index:

B: General

Division name: 01 IC

Category 1:

17 ASSP

Category 2:

2. Real-Time Clock

Product name: Overall

Related documents:

Question:

What are the notes for time settings (S3511/S3530/S3531)?

Answer:

If time data is rewritten in a product with an alarm interrupt (S-3511/S-3530/S-3531), be sure to disable

the alarm interrupt before the time is set.

Reason: When data is written using real-time data access 2, registers for hours, minutes, and seconds

are reset (all "0"'s), and arbitrary hours, minutes, and seconds are then set. If the alarm is set for 0:00

a.m. and the alarm interrupt is enabled, when the time data is rewritten the registers are reset (all "0"'s)

to 0:00 a.m., the set alarm time, thereby causing an interrupt (INT).

FAQ No.: 17S35004

Collection of Product FAQs

Author: Shirai Masaaki

Date: 99/04/14 (Wednesday) 11:34 (modified: 99/05/18)

Public (Printing O.K.)

Index:

B: Technical

Division name: 01 IC

Category 1:

17 ASSP

Category 2:

2. Real-Time Clock

Cal No.:

Overall

Related documents:

Question:

What about the write/read errors (notes)?

Answer:

To continuously write or read data in a 3-wire RTC (S-3511/S-3513/S-35L12/S-3510), be sure to change

"CS" to "L" after the first command has been executed and before the next command is executed. If

commands are continuously executed without changing "CS" to "L," the second command is

disregarded.

Be sure to change
"CS" to "L."

SCK

SIO

Status data

LSB

MSB

Command

MSB

LSB

POWER

Time data

LSB

MSB

Command

MSB

LSB

FAQ No.: 17S35003

Collection of Product FAQs

Author: Shirai Masaaki

Date: 99/04/13 (Tuesday) 15:40 (modified: 99/05/18)

Public (Printing O.K.)

Index:

A: General

Division name: 01 IC

Category 1:

17 ASSP

Category 2:

2. Real-Time Clock

Cal No.:

Overall

Related documents:

Question:

What about the Y2K problem?

Answer:

Our Real-Time Clock outputs information consisting of the last two digits of the year. The S-35L12/L32

can use the register bits in its RTC to determine whether the year is 1900 or 2000 when the last two

digits change from 99 to 00. Most other RTCs, however, cannot determine whether the year is 1900 or

2000 when the last two digits change from 99 to 00. Thus, when this microcomputer is used, the user

must load year information for the RTC in a microcomputer to determine whether the year is 1900 or

2000. Accordingly, when the year reaches 2000, our RTC allows year information to operate normally

and be output as "00," thereby preventing malfunctions.

There is no problem with the operation of the IC. If, however, peripheral circuits and software

developed by a client manage year information using the last two digits of the year, they may

malfunction. Thus, such devices should be checked.

http://www.sii.co.jp/sii2000.htm

FAQ No.: 17S35002

Collection of Product FAQs

Author: Shirai Masaaki

Date: 99/04/13 (Tuesday) 14:26 (modified: 99/04/13)

Public (Printing O.K.)

Index:

A: General

Division name: 01 IC

Category 1:

17 ASSP

Category 2:

2. Real-Time Clock

Cal No.:

Overall

Related documents:

Question:

Why is an auto calendar available through the year 2099?

Answer:

The SII's RTC denotes the year using its last two digits. These digits are then divided by four, and if

they are divisible the year is determined to be a leap year (the auto calendar determines both 1996 and

2000 to be leap years). The actual calendar, however, does not treat a year with "00" as its last two

digits as a leap year (except for the year 2000; see the following). Accordingly, although 2100 is not a

leap year, the RTC treats it as one. Therefore, this auto calendar is available through 2099.

(Note) A year is defined as a leap year when its last two digits are "00" and its first two digits are

divisible by four.

FAQ No.: 17S35001

Part Number S-3510