S1C62N82 TECHNICAL HARDWARE
EPSON
I-67
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (SVD Circuit and Heavy Load Protection Function)
Notice that even if the SVD circuit detects a drop in the
supply voltage (1.2 V/2.4 V or less) and invokes the heavy
load protection mode, this will be the same as when the
software invokes the heavy load protection mode, in that the
SVD circuit will be sampled with a timing synchronized to
the 2 Hz output from the prescaler. If the SVD circuit
detects a voltage drop and enters the heavy load protection
mode, it will return to the normal mode once the supply
voltage recovers and the SVD circuit determines that the
supply voltage is 1.2 V/2.4 V or more.
The S1C62N82 has a heavy load protection function for
when the battery load becomes heavy and the supply voltage
drops, such as when a melody is played or an external lamp
lights. This functions works in the heavy load protection
mode. The normal mode changes to the heavy load protec-
tion mode in the following two cases:
When the software changes the mode to the heavy load
protection mode
When the SVD circuit detects a supply voltage less than
2.4 V (S1C62N82/62A82) or 1.2 V (S1C62L82), in which
case the mode is automatically changed to the heavy load
protection mode
Based on the operation of the SVD circuit and the heavy
load protection function, the S1C62L82 obtains an opera-
tion supply voltage as low as 0.9 V. See the electrical char-
acteristics for the precision of voltage detection by the SVD
circuit.
In the heavy load protection mode, the internally regulated
voltage is generated by the liquid crystal driver supply
output, VL2, in order to operate the internal circuit. Conse-
quently, more current is consumed in the heavy load protec-
tion mode than in the normal mode. Unless necessary, do
not select the heavy load protection mode with the software.
Activation of the SVD circuit by software in the heavy load protec-
tion mode causes a malfunction. Avoid such activation if possible.
Note
Operation of heavy
load protection
function