em78f644nso28s ELAN Microelectronics Corp, em78f644nso28s Datasheet - Page 65

• Manufacturer Part Number: em78f644nso28s
• Description: Flash Series 8-bit Microcontroller
• Manufacturer: ELAN Microelectronics Corp

Product Specification (V1.0) 05.05.2010
(This specification is subject to change without further notice)
1
2
Bit 5 (TC1SS): TC1 clock source select bit
(Normal Mode Source)
455K, 4M, 8M, 16 MHz
continue to work in Normal/Green mode.
The oscillator stable time depends on the oscillator characteristics
After the oscillator has stabilized, the CPU will count 254/32 CLK in Normal/Green mode and
Ex 1: The 4 MHz IRC Wakes-up from Sleep mode to Normal mode. The total Wake-up time
Ex 2: The 4 MHz IRC Wakes-up from Sleep mode to Green mode. The total wake-up time is
CPU Operation Mode
1M ~ 16 MHz
Oscillator
is 2 µs + 32 CLK @ 4 MHz
100 µs + 32 CLK @ 16kHz
Crystal ;
3.5 MHz
ERC ;
IRC ;
0: Fs is used as Fc
1: Fm is used as Fc
Figure 6-7 CPU Operation Mode Block Diagram
Sleep/Idle → Normal
Green → Normal
Sleep/Idle → Green
Sleep/Idle → Normal
Green → Normal
Sleep/Idle → Green
Sleep/Idle → Normal
Green → Normal
Sleep/Idle → Green
CPU Mode Status
EM78F648/644/642/641/548/544/542/541N
Oscillator Stable Time
0.5 ms ~ 2 ms
< 100 µs
< 100 µs
< 100 µs
< 5 µs
< 2 µs
(S)
1
8-Bit Microcontroller
Normal/Green
Count from
254 CLK
254 CLK
(CLK)
32 CLK
32 CLK
32 CLK
2
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