Panasonic KX-B620 - Page 41

KX-B620 Series
KX-B520 Series
2.2 Reset Signal Circuit
1) Function
When the power is turned on, or when the power is momentarily interrupted, reset pulses are
generated to reset the CPU.
2) Circuit Operation MOS
When the power is turned on and the power source Vcc increases to exceed +4.25 V, Reset IC (C101)
is activated, “L” signal is sent for about 3.3 ms and “H” is sent to reset the CPU (6-pin) .
When the power is momentarily interrupted and power source goes down below +4.25 V, “L” signal
is sent to stop the CPU. When the power is resumed and power source increases to exceed +4.25 V,
“L” signal is sent for about 3.3 ms and “H” is sent to reset the CPU again.
Circuit diagram and timings are as follows:
(IC 101) CPU (IC 102)
M51953
Fig. 12 Circuit Diagram