MA300012 Microchip Technology, MA300012 Datasheet - Page 22

• Manufacturer Part Number: MA300012
• Description: MODULE DSPIC30F SAMPLE 64QFP
• Manufacturer: Microchip Technology

Specifications of MA300012

• Module/board Type: dsPIC30F Plug-in Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: DM240001
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

dsPIC30F
FIGURE 7-1:
7.4
There are two internal timers that offer necessary
delays on power-up. One is the Power-up Timer
(PWRT), which provides a delay on power-up only. The
PWRT keeps the part in Reset while the power supply
stabilizes. The other is the Oscillator Start-up Timer
(OST), intended to keep the chip in Reset until the
crystal oscillator is stable. With these two timers on-
chip, most applications need no external Reset
circuitry.
DS70043F-page 20
SOSCO
SOSCI
OSC1
OSC2
Programmable Power-up Timer
(PWRT)
Internal Fast
RC (FRC)
Secondary
Oscillator
Oscillator
Oscillator
OSCILLATOR SYSTEM BLOCK DIAGRAM
Primary
32 kHz
Internal Low
(LPRC) Osc
x4, x8, x16
Power RC
PLL
Secondary Osc
Primary Osc
PLL
7.5
An Oscillator Start-up Timer (OST) is included to
ensure that a crystal oscillator (or ceramic resonator)
has started and stabilized. The OST is a simple 10-bit
counter that counts 1024 TOSC cycles before
releasing the oscillator clock to the rest of the system.
The time-out period is designated as TOST. The TOST
time is involved every time the oscillator has to restart
(i.e., on Power-On Reset (POR), Brown-Out Reset
(BOR) and wake-up from Sleep). The oscillator start-up
timer is applied to the LP oscillator, XT, XTL and HS
modes (upon wake-up from Sleep, POR and BOR) for
the primary oscillator.
Switching
Oscillator Start-up Timer/Stabilizer
(OST)
Control
Clock
Block
and
F
OSC
© 2005 Microchip Technology Inc.
To Timer1
Programmable
Divider
Clock
4 x F
CY