EM78159NAS EMC [ELAN Microelectronics Corp], EM78159NAS Datasheet - Page 37

• Manufacturer Part Number: EM78159NAS
• Description: 8-Bit Microcontroller with OTP ROM
• Manufacturer: EMC [ELAN Microelectronics Corp]

Product Specification (V1.0) 03.10.2006
(This specification is subject to change without further notice)
4.11 Residue-Voltage Protection
When the battery is replaced, device power (Vdd) is cut off but residue-voltage
remains. The residue-voltage may trips below minimum Vdd, but not to zero. This
condition may cause a poor power-on reset. The following figures illustrate two
recommended methods on how to build a residue-voltage protection circuit for
EM78P159N.
EM78P159N
EM78P159N
/RESET
/RESET
Figure 4-11a Residue Voltage Protection Circuit (1)
Figure 4-11b Residue Voltage Protection Circuit (2)
Vdd
Vdd
40K
40K
Q1
Q1
10K
1N4684
8-Bit Microcontroller with OTP ROM
33K
R1
R2
Vdd
Vdd
EM78P159N
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