SN8P1602B
8-Bit Micro-Controller
SYSTEM MODE DESCRIPTION
OVERVIEW
The chip is featured with low power consumption by switching around four different modes as following.
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High-speed mode
Low-speed mode
Power-down mode (Sleep mode)
Green mode
NORMAL MODE
In normal mode, the system clock source is external high-speed clock. After power on, the system works under normal
mode. The instruction cycle is fosc/4. When the external high-speed oscillator is 3.58MHz, the instruction cycle is
3.58MHz/4 = 895KHz. From normal mode, the system can get into power down mode, slow mode and green mode.
SLOW MODE
In slow mode, the system clock source is internal low-speed RC clock. To set CLKMD =1, the system switches into
slow mode. In slow mode, the system functions similar to the normal mode except using the internal RC clock. The
system in slow mode can switch back to high-speed normal mode. On the other hand, it can be easily switch to power
down mode and green mode for less power consumption.
GREEN MODE
The green mode provides a time-variable wakeup function. Users can decide wakeup time by setting TC0 timer. There
are two paths into green mode. One is from normal mode and the other is from slow mode. In normal mode, the TC0
timer overflow time is very short. In slow mode, the overflow time is longer. Users can select appropriate situation for
their applications. Under green mode, the power consumption is around 5uA in 3V condition. The system can be
waked up to last system mode by TC0 timer timeout and P0 trigger signal.
POWER DOWN MODE
The power down mode is also called sleep mode. The MCU stops working as sleeping status. To set CUPM0 = 1, the
system gets into power down mode. The external high-speed and low-speed oscillators are turned off. The system can
be waked up by P0, P1 trigger signal.
SONiX TECHNOLOGY CO., LTD
Page 44
Version 1.2