Z8F082ASH020SC datasheet(46/244 Pages) ZILOG

46 / 244 page

PS024705-0405

P R E L I M I N A R Y

Low-Power Modes

Z8 Encore! XP® F08xA Series

Product Specification

Low-Power Modes

Overview

The Z8 Encore! XP® F08xA Series products contain power-saving features. The highest

level of power reduction is provided by the STOP mode. The next lower level of power

reduction is provided by the HALT mode.

Further power savings can be implemented by disabling individual peripheral blocks

while in Normal mode.

STOP Mode

Executing the eZ8 CPU’s STOP instruction places the device into STOP mode. In STOP

mode, the operating characteristics are:

• Primary crystal oscillator and internal precision oscillator are stopped; XIN and XOUT (if

previously enabled) are disabled, and PA0/PA1 revert to the states programmed by the

GPIO registers

• System clock is stopped

• eZ8 CPU is stopped

• Program counter (PC) stops incrementing

• Watch-Dog Timer’s internal RC oscillator continues to operate if enabled by the Oscillator

Control Register

• If enabled, the Watch-Dog Timer logic continues to operate

• If enabled for operation in STOP mode by the associated Flash Option Bit, the Voltage-

brown out protection circuit continues to operate

• Transimpedance amplifier in the ADC block continues to operate if enabled by the Power

Control Register to do so; all other portions of the ADC are disabled

• All other on-chip peripherals are idle

To minimize current in STOP mode, all GPIO pins that are configured as digital inputs

must be driven to one of the supply rails (VCC or GND). The device can be brought out of

STOP mode using STOP Mode Recovery. For more information about STOP Mode

Recovery refer to “Reset and STOP Mode Recovery” on page 19.

Z8F082ASH020SC датащи(PDF) 46 Page - Zilog, Inc.