REV.-A
2.3.1.4 ST-RAM (7A) Battery Backup
The ST-RAM (7A) employs a lithium battery (3.00 to 3.35 VDC) for backup, and is used to maintain the initial
data for the printer mechanism and settings for the control panel when the printer power is turned off.
Figure 2-28 shows the ST-RAM (7A) battery backup circuit, and Table 2-21 shows the ST-RAM conditions
when the power is turned on or off.
R58
J
R59.
/
Vss
(7A)
Figure 2-28. Battery Backup Circuit
When the power is turned on under normal conditions, +5 V is applied to
of the ST-RAM, and the CPU
starts read/write operations. When the power is turned off, and the voltage on the +5 V line drops to about
3.3 V or less, transistors
and
turn off, and the voltage from the lithium battery
is applied to
the
terminal of the ST-RAM. In this way, the data in the ST-RAM is maintained.
When the voltage from the lithium battery
the initial data for the printer mechanism and settings for
the control panel are cleared, and default values are set at power is turned on.
Table
ST--RAM Conditions with Power On/Off
Printer Power
+5 V
Line
(Pin 26)
[V]
ST-RAM Mode
OFF
L
L
2.4- 2.7
Data holding
ON
H
H
+ 5
Normal
I
2-33
Summary of Contents for LQ-1060
Page 1: ...EPSON TERMINAL PRINTER L Q 8 6 0 1 0 6 0 TECHNICAL MANUAL ...
Page 5: ...REVISION TABLE REVISION DATE ISSUED I CHANGE DOCUMENT I I 1st issue I v ...
Page 68: ...cc o REV A N N n 1 cc b I al cc u co n4 2 1 Figure 2 14 Main Switching 2 21 ...
Page 79: ...REV A Table 2 20 State of Module 1 1 I W stay E H H L H d O s H H 4 2 32 ...
Page 203: ...Figure 5 6 MONPS MONPSE Board Voltage Waveforms 5 17 ...
Page 204: ...REV A Fiaure 5 6 MONPS MONPSE Board Voltage Waveforms z L 5 18 ...
Page 205: ...Figure 5 6 MONPS MONPSE Board Voltage Waveforms 5 19 ...
Page 248: ...REV A A 3 DRAWINGS 3 J32 J TI g 4 Figure A 27 MONPS Board Component Layout A 34 ...
Page 250: ... 2 1 1 1 1 I A b 2 Ozaz 1202 C O ZZH Z UOEE vu I 1 Figure A 29 MONPS Board Circuit Diagram ...
Page 252: ...L t g Figure A 31 JUNMM Board Component Layout A 38 ...