Functions For Power Failure And Motor Lock - Sharp ER-1910 Service Manual

4-9. Drawer control
[Without option drawer]
VPO
2SD1509 |
R4
SC 10838 C
Drawer
open
sensor
Fig. 4-21
The DR signal output from the pin 35 of the SC1033 drives Q2 to
apply current to the drawer magnet. D1 is used to prevent a
counter-electromotive force.
[With délion drawers] 7
Option drawer
B,D,E
yO 0
Drawer A
—o , Drawer
"7 open
—3 sensor
: A
Fig. 405° VPO{2}-—
In case an optional drawer is in use, drawers are driven by the DR
signal issued from the pin 35 of the SC1033C and MG1 through MG4.
A spark killer diode is contained in the M54532P.
4-10. Power supply circuit
VH1, VH2
VDISP
VCC
VDD
GND
SOHOS
Converter
Joyeinbe
Fig. 4-23
~ VPO : Drawer +17. 6V~—19. ov
VP : Printer +18V — :
VH1, VH2 : Display heater +3.5V (rms)
-VDISP>: Display tube plate and grid +34V (+28.8V~+37.4V)
VCC : Circuit drive +5V (+4.5V~+5.5V)
VB : Power off time CPU & KDC drive +3.6V, min.
VDD
- Power supply to CPU and KDC +5V (+4,5V~+5.5V)
C20 i ~ ggy—_|- —_~Svre
t C18 :
| _§ Drawer OV
a a a ee
| 6) As Q10 turns off, VPO then starts to drop. -
ER=2395
VPO circuit:
VPO Q10 2SD1191 TH
PO
vO
0 0 >
Mode switch] p11
C17].
C14:|C18.
1) The base voltage is not applied to Q10 when VO is not shorted
with P-ON within the mode switch (power. of Q10 is atthe OFF
state.
2) When VO is shorted with P- ON, base voltage is ; added to Qto
so that it goes active. _
3) With an active state of Q10, the voltage VPO starts to rise.
4) When the voltage at point @ @) 'reaches: TOV" via 'R27, (202 then
comes active.
5) If the base voltage is added to ag in this moment
on and Q10.turns off. fee
; 98 i is turned
7) As VPO starts dropping, it also causes i pase > voltage to
decrease and Q9 turns off, finally... si! Hoary
8) Q10 starts to rise. again and VPO. paging: to rise. :
9) .VPO is controlled stable by repeating the-above eos, ay thru 18).
5. Power failure/motor lock mechanical .
action and measures |
5-1. Action at power failure (power off)
When the power is turned off in a middle of printing operation due
to a power failure, the CPU executes the power failure process.
(1) When a power failure is encountered during printing operation,
power failure marks (.....) are printed on a next line upon the
recovery of power, and the printout lost at the time of power
failure is correctly produced on a next line. :
(2) If power failure was met other than during printing operation,
the operation resumes in succession to the operation suspended
at the time of power-failure, when the | power supply is recovered.
15-02-87
Printout before power failure
— Power failure marks
14999. 99 ee
Printout of the data immediately
_ before the power failure.
1 @Q
*999.99TR
144)
000-0020