Disabling The Lvi Operation - NEC V850ES/F 3-L Series User Manual

32-bit single-chip microcontroller

Table of Contents

Low-Voltage Detector

22.4.3 Disabling the LVI operation

Supply voltage

LVI detection

POC detection

: Delay of analog circuitry

Operation timing of Low-Voltage Detector (LVIM.LVIMD = 0)

If VDD is fluctuating around the LVI detection level (VLVI), note that the

judgment upon the INTLVIH or INTLVIL interrupt servicing may be incorrect.

For example, if during INTLVIL interrupt servicing multiple INTLVIH/INTLVIL

interrupts are generated due to the VDD fluctuation, it cannot be detected

which interrupt was generated last. Consequently, when INTLVIL interrupt

servicing is performed at the last, even though VDD > VLVI, software detects

VDD < VLVI by mistake.

Therefore when LVI detection interrupt servicing is performed, program the

software code as to complete interrupt servicing before the next LVI detection

is generated, at the same time as controlling the VDD, or monitoring the LVIF

1. Mask the interrupt INTLVIH by setting LVIHMK to 1.

2. Disable the LVI operation by setting the LVIM. LVON bit to 0.

3. Clear the interrupt request flag LVIHIF of the INTLVIH register.

User's Manual U18743EE1V2UM00