Preliminary
SN8P1702A/SN8P1703A
8-bit micro-controller build-in 12-bit ADC
SYSTEM MODE DESCRIPTION
OVERVIEW
The chip is featured with low power consumption by switching around three different modes as following.
ꢀ
ꢀ
ꢀ
ꢀ
High-speed mode
Low-speed mode
Power-down mode (Sleep mode)
Green mode
In actual application, the user can adjust the chip’s controller to work in these three modes by using OSCM register. At
the high-speed mode, the instruction cycle (Fcpu) is Fosc/4. At the low-speed mode and 3V, the Fcpu is 16KHz/4.
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. All software and hardware are executed and working. In normal mode, system can get into
power down mode and slow mode.
SLOW MODE
In slow mode, the system clock source is internal low-speed RC clock. To set CLKMD = 1, the system switch to slow
mode. In slow mode, the system works as normal mode but the slower clock. The system in slow mode can get into
normal mode and power down mode. To set STPHX = 1 to stop the external high-speed oscillator, and then the system
consumes less power.
GREEN MODE
The green mode is a less power consumption mode. Under green mode, there are only TC0 still counting and the other
hardware stopping. The external high-speed oscillator or internal low-speed oscillator is operating. To set CPUM1 = 1
and CPUM0 = 0, the system gets into green mode. To set TC0GN = 1 (bit 1 of T0M) will enable TC0 green mode
wakeup function. The system can be waked up to last system mode by TC0 timer timeout and P0 trigger signal.
The green mode provides a time-variable wakeup function. Users can decide wakeup time by setting TC0 timer. There
are two channels into green mode. One is normal mode and the other is 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 5u amp in 3V condition.
POWER DOWN MODE
The power down mode is also called sleep mode. The chip stops working as sleeping status. The power consumption
is very less almost to zero. The power down mode is usually applied to low power consuming system as battery power
productions. 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 48
Revision 0.5
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