R2023K datasheet(18/50 Pages) RICOH

18 / 50 page

R2023K/T

• Oscillation Adjustment Register (Address 7h)

DEV

(For Writing)

DEV

(For Reading)

Default Settings *)

Default settings:

Default value means read / written values when the PON bit is set to “1” due to VDD

power-on from 0 volts.

DEV bit

When DEV is set to 0, the Oscillation Adjustment Circuit operates 00, 20, 40 seconds.

When DEV is set to 1, the Oscillation Adjustment Circuit operates 00 seconds.

F6 to F0 bits

The Oscillation Adjustment Circuit is configured to change time counts of 1 second on the basis of the

settings of the Oscillation Adjustment Register at the timing set by DEV.

* The Oscillation Adjustment Circuit will not operate with the same timing (00, 20, or 40 seconds)

as the timing of writing to the Oscillation Adjustment Register.

* The F6 bit setting of 0 causes an increment of time counts by ((F5, F4, F3, F2, F1, F0) - 1) x 2.

The F6 bit setting of 1 causes a decrement of time counts by (( F5,F4,F3,F2,F1,F0 ) + 1) x 2.

The settings of "*, 0, 0, 0, 0, 0, *" ("*" representing either "0" or "1") in the F6, F5, F4, F3, F2, F1, and F0

bits cause neither an increment nor decrement of time counts.

Example:

If (DEV, F6, F5, F4, F3, F2, F1, F0) is set to (0, 0, 0, 0, 0, 1, 1, 1), when the second digits read 00, 20, or 40, an

increment of the current time counts of 32768 + (7 - 1) x 2 to 32780 (a current time count loss).

If (DEV, F6, F5, F4, F3, F2, F1, F0) is set to (0, 0, 0, 0, 0, 0, 0, 1), when the second digits read 00, 20, 40, neither

an increment nor a decrement of the current time counts of 32768.

If (DEV, F6, F5, F4, F3, F2, F1, F0) is set to (1, 1, 1, 1, 1, 1, 1, 0), when the second digits read 00, a decrement of

the current time counts of 32768 + (- 2) x 2 to 32764 (a current time count gain).

An increase of two clock pulses once per 20 seconds causes a time count loss of approximately 3 ppm (2 / (32768

x 20 = 3.051 ppm).

Conversely, a decrease of two clock pulses once per 20 seconds causes a time count gain of

3 ppm.

Consequently, when DEV is set to “0”, deviations in time counts can be corrected with a precision of

±1.5

ppm.

In the same way, when DEV is set to “1”, deviations in time counts can be corrected with a precision of

±0.5

ppm.

Note that the oscillation adjustment circuit is configured to correct deviations in time counts and not the

oscillation frequency of the 32.768-kHz clock pulses.

For further details, see "P33

Configuration of Oscillation

Circuit and Correction of Time Count Deviations

• Oscillation Adjustment Circuit".

R2023K Datasheet(PDF) 18 Page - RICOH electronics devices division

R2023K Datasheet(HTML) 18 Page - RICOH electronics devices division

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

Datasheet Download

Link URL