Motorola V975 Service Manual

Motorola Confidential Proprietary
V975/V980Theory of Operation
3-18
Draft 1.0
Clock Generation
PCAP can generate a 32kHz clock either from an in-
ternal RC Oscillator or an external crystal. The internal
RC oscillator doesn’t provide the stability that the Rain-
bow requires for optimal performance, therefore, an
external 32.768kHz crystal is used.
The PGM2 pin of PCAP is tied to LCELL_BYP, to
prevent the internal RC oscillator from being routed to
the 32kHz pin under any circumstances. The 32kHz
oscillator will run at all times. It is powered by LCELL,
a coincell battery that is also used to maintain the real
time clock. The phone will only power up when the
32kHz becomes stable.
Debounce
Logic
8x PLL
Control
Logic
32kHz
Oscillator
Clock
Detect
PCAP
32kHz
RC
Oscillator
32out_en
Xtal1
Xtal2
Figure 3-24. RTC Clock
Baseband Electrical (Digital)

Motorola V975 Specifications

General

Brand	Motorola
Model	V975
Category	Cell Phone
Language	English