Nxp Semiconductors UM10237 ユーザーズマニュアル

UM10237_2

© NXP B.V. 2008. All rights reserved.

and resume operation. The alarm output has a nominal voltage swing of 1.8 V. Note that 
the PLL is disabled when waking up from power down. See 

 for the PLL 

start-up procedure.

 

 

CCLK

INTERRUPT GENERATOR

COUNTER INCREMENT

INTERRUPT ENABLE

ALARM MASK

REGISTER

counter

enables

CLK1

REFERENCE CLOCK DIVIDER

(PRESCALER)

CLK32k

strobe

COMPARATORS

CLOCK GENERATOR

ALARM

REGISTERS

TIME COUNTERS

RTC OSCILLATOR

MUX

ALARM

O

Alarm output (see 

RTCX1

I

Input to the RTC oscillator circuit.

RTCX2

O

Output from the RTC oscillator circuit.

If the RTC is not used, the RTCX1/2 pins can be left 

floating.

VBAT

I

 3.3 V on this pin supplies the power to the 

RTC.

If the RTC is used, VBAT must be connected to either pin 

V

DD(3V3)

 or an independent power supply (external battery). 

Otherwise, VBAT should be left floating.