AB18X5 Real-Time Clock with Power

Management Family

Date of Issue: October 16, 2014

3.0 x 3.0 mm

Page 9 of 37

Abracon Drawing #453568

Revision: C

PSW/nIRQ2

Secondary interrupt output connection. It is an open drain output. This pin can be left floating if not

used. PSW/nIRQ2 may be configured to generate several signals as a function of the OUT2S field (see

0x11 - Control2). This pin will be configured as an ~1 Ω switch if the PWR2 bit is set.

1. PSW/nIRQ2 can drive the value of the OUTB bit.

2. PSW/nIRQ2 can drive the square wave output (see 0x13 - SQW) if enabled by SQWE.

3. PSW/nIRQ2 can drive the inverse of the combined interrupt signal IRQ(see Interrupts).

4. PSW/nIRQ2 can drive the inverse of the alarm interrupt signal AIRQ(see Interrupts).

5. PSW/nIRQ2 can drive either sense of the timer interrupt signal TIRQ.

6. PSW/nIRQ2 can function as the power switch output for controlling the power of external devices

(see Sleep Control).

nTIRQ (only available in

Timer interrupt output connection. It is an open drain output. nTIRQ always drives the active low nTIRQ

signal. If this pin is used, an external pull-up resistor must be added to this pin. If the pin is not used, it

can be left floating.

CLKOUT/nIRQ3

Square Wave output connection. It is a push-pull output, and may be configured to generate one of two

signals.

1. CLKOUT/nIRQ3 can drive the value of the OUT bit.

2. CLKOUT/nIRQ3 can drive the square wave output (see 0x13 - SQW) if enabled by SQWE.

nRST

External reset output connection. It is an open drain output. If this pin is used, an external pull-up resis-

tor must be added to this pin. If the pin is not used, it can be left floating.The polarity is selected by the

RSP bit, which will initialize to 0 on power up to produce an active low output. See Autocalibration Fail

Interrupt ACIRQ for details of the generation of nRST.

Table 3: Pin Descriptions

Pin Name

Description