PCF2131 datasheet(48/85 Pages) NXP

48 / 85 page

NXP Semiconductors

PCF2131

Nano-power highly accurate RTC with integrated quartz crystal

Bits labeled as T are unused and return 0 when read.

Bit

Symbol

Value

Description

MIA/B

minute interrupt mask

SIA/B

second interrupt mask

WD_CDA/B

watchdog interrupt mask

AIEA/B

alarm interrupt mask

BIEA/B

battery flag interrupt mask

BLIEA/B

battery low flag interrupt mask

Table 81. INT_A/B_MASK1 - interrupt mask 1 register (address 31h/33h) bit description...continued

Bits labeled as T are unused and return 0 when read.

Bit

Symbol

INT_A/B_MASK2

Reset

value

Table 82. INT_A/B_MASK2 - interrupt mask 2 register (address 32h/34h) bit allocation

Bits labeled as T are unused and return 0 when read.

Bit

Symbol

Value

Description

7 to 4

0000

unused

TSIE1A/B

time stamp 1 interrupt mask

TSIE2A/B

time stamp 2 interrupt mask

TSIE3A/B

time stamp 3 interrupt mask

TSIE4A/B

time stamp 4 interrupt mask

Table 83. INT_A/B_MASK2 - interrupt mask 2 register (address 32h/34h) bit description

The registers at addresses 31h to 32h are used to configure interrupt source for INTA pin, and the registers at

addresses 33h to 34h are for INTB pin.

All of above interrupts could be masked from either INTA or INTB, with corresponding bit set to ‘1’, as shown in

Figure 17.

7.14 External clock test mode

A test mode is available which allows on-board testing. In this mode, it is possible to set up test conditions and

control the operation of the RTC.

The test mode is entered by setting bits COF[2:0] logic 111 (register CLKOUT_ctl) and bit EXT_TEST logic 1

(register Control_1). Then pin CLKOUT becomes an input. The test mode replaces the internal clock signal

(8192 Hz) with the signal applied to pin CLKOUT. Every 8192 positive edges applied to pin CLKOUT generate

an increment of one second.

The signal applied to pin CLKOUT should have a minimum pulse width of 300 ns and a minimum period of 1

000 ns. The internal clock, now sourced from CLKOUT, is divided down by a divider chain called prescaler. The

PCF2131

All information provided in this document is subject to legal disclaimers.

Product data sheet

Rev. 2.0 — 5 October 2023

48 / 85

PCF2131 Datasheet(PDF) 48 Page - NXP Semiconductors

PCF2131 Datasheet(HTML) 48 Page - NXP Semiconductors

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 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85

Datasheet Download

Link URL