EM78P510N
8-Bit Microcontrollers
6.7.2 Residue-Voltage Protection
When battery is replaced, device power (Vdd) is taken off but residue-voltage remains.
The residue-voltage may trips below Vdd minimum, but not to zero. This condition may
cause a poor power-on reset. Fig.6-13 and Fig.6-14 show how to build a
residue-voltage protection circuit.
VDD
VDD
33K
Q1
10K
/RESET
100K
1N4684
Fig. 6-13 Residue Voltage Protection Circuit 1
Fig. 6-14 Residue Voltage Protection Circuit 2
Product Specification (V0.9) 09.12.2006
(This specification is subject to change without further notice)
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