DSPIC30F datasheet(137/220 Pages) MICROCHIP

137 / 220 page

 2004 Microchip Technology Inc.

Preliminary

DS70116C-page 135

dsPIC30F5011/5013

20.0

SYSTEM INTEGRATION

There are several features intended to maximize sys-

tem reliability, minimize cost through elimination of

external components, provide Power Saving Operating

modes and offer code protection:

• Oscillator Selection

• Reset

- Power-on Reset (POR)

- Power-up Timer (PWRT)

- Oscillator Start-up Timer (OST)

- Programmable Brown-out Reset (BOR)

• Watchdog Timer (WDT)

• Power Saving Modes (Sleep and Idle)

• Code Protection

• Unit ID Locations

• In-Circuit Serial Programming (ICSP)

dsPIC30F devices have a Watchdog Timer which is

permanently enabled via the configuration bits or can

be software controlled. It runs off its own RC oscillator

for added reliability. There are two timers that offer

necessary delays on power-up. One is the Oscillator

Start-up Timer (OST), intended to keep the chip in

Reset until the crystal oscillator is stable. The other is

the Power-up Timer (PWRT) which provides a delay on

power-up only, designed to keep the part in Reset while

the power supply stabilizes. With these two timers

on-chip, most applications need no external Reset

circuitry.

Sleep mode is designed to offer a very low current

Power-down mode. The user can wake-up from Sleep

through external Reset, Watchdog Timer Wake-up, or

through an interrupt. Several oscillator options are also

made available to allow the part to fit a wide variety of

applications. In the Idle mode, the clock sources are

still active but the CPU is shut-off. The RC oscillator

option saves system cost while the LP crystal option

saves power.

20.1

Oscillator System Overview

The dsPIC30F oscillator system has the following

modules and features:

• Various external and internal oscillator options as

clock sources

• An on-chip PLL to boost internal operating

frequency

• A clock switching mechanism between various

clock sources

• Programmable clock postscaler for system power

savings

• A Fail-Safe Clock Monitor (FSCM) that detects

clock failure and takes fail-safe measures

• Clock Control register (OSCCON)

• Configuration bits for main oscillator selection

Configuration bits determine the clock source upon

Power-on Reset (POR) and Brown-out Reset (BOR).

Thereafter, the clock source can be changed between

permissible clock sources. The OSCCON register con-

trols the clock switching and reflects system clock

related status bits.

Table 20-1 provides a summary of the dsPIC30F Oscil-

lator Operating modes. A simplified diagram of the

oscillator system is shown in Figure 20-1.

DSPIC30F 数据表(PDF) 137 Page - Microchip Technology

DSPIC30F 数据表(HTML) 137 Page - Microchip Technology

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 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载