e-STUDIO170F Circuit Description
January 2005 © TOSHIBA TEC
7 - 30
7.3.5
Reset Circuit
Fig.7-23
When the logic voltage is unstable as the power switch is turned on, and so on, or an abnormal condi-
tion has occurred in the system, the reset circuit resets the respective IC’s to prevent them from mal-
functioning.
When the voltage of 3.3V delivered from the LVPS is 2.9V or under, the PWRESETX signal output from
the Reset IC (IC42) will go LOW. This causes the RESETX signal output from the AND (IC18) to go
LOW to reset the entire system including the ASIC (Engine controller: IC15), and USB controller (IC49).
Also, when the PWRESETX signal goes LOW, Q108 will be turned on and reset the Main-CPU (IC22).
In case an abnormal condition has occurred in the system and the Main-CPU crashes, the ASIC
causes the ROUTX signal to go LOW to turn on Q108. This causes the RESETX signal to go LOW to
reset the entire system.
Signal Name
Type
Active
Description
Destination
PWRESETX
O
L
Power ON reset signal
IC19
RESETX
I
L
Reset signal
Each IC
ROUTX
O
L
Watchdog reset signal
IC5
3.3V
3.3V
Main PBA
36
37
5
RESETX
5VRESX
ROUTX
1
4
IC42
Reset IC
IC15
ASIC
(Engine controller)
IC22
Main-CPU
Q108
10
R213
C206
IC19
IC18
Flash ROM (IC23: Pin12)
USB controller (IC49: Pin46 (via AND))
ASIC (I/O port: IC38: Pin70)
DSC (IC27: Pin32)
ASIC (I/O port for operation panel: IC4: Pin70)
PWRESETX
2
3.3V
R274
2
13
4
2
1
4
7
1
IC31
Bus transceiver
(3.3V +5V)
Содержание ESTUDIO170F
Страница 1: ...SERVICE MANUAL PLAIN PAPER FACSIMILE e STUDIO170F File No SME04002900 R04102171300 TTEC Ver01_2005 05 ...
Страница 2: ... 2005 TOSHIBA TEC CORPORATION All rights reserved ...
Страница 192: ...e STUDIO170F Function Settings January 2005 TOSHIBA TEC 4 132 ...
Страница 214: ...e STUDIO170F Mechanical Description January 2005 TOSHIBA TEC 5 22 ...
Страница 308: ...e STUDIO170F Circuit Description January 2005 TOSHIBA TEC 7 78 ...
Страница 372: ...e STUDIO170F Removal Replacement Adjustment January 2005 TOSHIBA TEC 8 64 ...
Страница 490: ...e STUDIO170F Appendix January 2005 TOSHIBA TEC 12 8 ...
Страница 491: ......
Страница 492: ......