RTC/TCXO/Crystal

Maxim Integrated

19

DS3231

Revision History

REVISION

NUMBER

REVISION

DATE

DESCRIPTION

PAGES

CHANGED

0

1/05

Initial release.

—

Changed Digital Temp Sensor Output from

±2°C to ±3°C.

1, 3

Updated Typical Operating Circuit.

1

2, 3, 4

1

2/05

Updated Block Diagram.

8

Added “UL Recognized” to Features; added lead-free packages and removed S from

top mark info in Ordering Information table; added ground connections to the N.C. pin

in the Typical Operating Circuit.

1

to 2.45V.

2

Added aging offset specification.

3

Relabeled TOC4.

7

Added arrow showing input on X1 in the Block Diagram.

8

9

10

Figure 1: Added sign bit to aging and temperature registers; added MSB and LSB.

11

Corrected title for rate select bits frequency table.

13

Added note that frequency stability over temperature spec is with aging offset register

= 00h; changed bit 7 from Data to Sign (Crystal Aging Offset Register).

14

Serial Data Bus section.

15

2

6/05

Modified the Handing, PC Board Layout, and Assembly section to refer to

J-STD-020 for reflow profiles for lead-free and leaded packages.

17

3

11/05

Changed lead-free packages to RoHS-compliant packages.

1

Changed

RST and UL bullets in Features.

1

2, 3

6

Added various conditions text to TOCs 1, 2, and 3.

7

RST.

9

Table 1: Changed column heading “Powered By” to “Active Supply”; changed

10

Indicated BBSQW applies to both SQW and interrupts; simplified temp convert

description (bit 5); added “output” to

INT/SQW (bit 2).

13

4

10/06

Changed the Crystal Aging section to the Aging Offset section; changed “this bit

indicates” to “this bit controls” for the enable 32kHz output bit.

14

Added Warning note to EC table notes; updated Note 12.

6

Updated the Typical Operating Characteristics graphs.

7

In the Power Control section, added information about the POR state of the time and

date registers; in the Real-Time Clock section, added to the description of the RST

function.

10

5

4/08

In Figure 1, corrected the months date range for 04h from 00–31 to 01–31.

11