Skip to main content
Knowledgebase
Home
Renesas Electronics Europe - Knowledgebase

What causes malfunction when MCU reverted after reset?

Latest Updated:03/01/2005

Question:

(Pin)   The CNVss pin and power source pin on the MCU were shorted, a malfunction occurred and the starting state of the MCU could be reverted to after a reset. What is the cause of this problem, and can this MCU be used as is? [2005/03/01]

Answer:

The MCU may be switched to single-chip mode or another mode (eg. the mode used for test operations during semiconductor manufacturing) by the voltage applied to the CNVss pin. Accordingly, when noise or improper voltage for the current mode is applied to the CNVss pin, the MCU may malfunction. For the correct applied voltage values, please refer to the datasheet or user's manual for your MCU.
MCU operation after a malfunction may be unstable. For example, malfunction may cause an input port to be switched to output, pins on the MCU may be broken or damaged due to current overflow, etc.
Accordingly, the quality of an MCU in such a situation cannot be guaranteed. (#104762)
Suitable Products
3803H
3803L
3823
3850A
3858
38D2
38D5
7544
7545
7546
7547
7548
7549