Information

PIC18F26K20/46K20
DS80000404H-page 6  2008-2013 Microchip Technology Inc.
16. Module: Resets (BOR)
An unexpected Reset may occur if the Brown-out
Reset module (BOR) is disabled, and then re-
enabled when the Fixed Voltage Reference is not
enabled (CVRCON2<7> = 0). This issue affects
BOR modes: BOREN<1:0> = 10 and
BOREN<1:0> = 01. In both of these modes, if the
BOR module is re-enabled while the device is
active, unexpected Resets may be generated.
Work around
If BOR is required, and power consumption is not
an issue, use BOREN<1:0> = 11. For
BOREN<1:0> = 10 mode, either switch to
BOREN<1:0> = 11 mode or enable the FVR
(CVRCON2<7> = 1) and verify that the FVR is
stable (CVRCON2<6> = 1) prior to entering Sleep.
If power consumption is an issue and low power is
desired, do not use BOREN<1:0> = 10 mode.
Instead, use BOREN<1:0> = 01 and follow the
steps below when entering and exiting Sleep.
1. Disable BOR by clearing
SBOREN(RCON<6> = 0) and the FVR
(CVRCON2<7> = 0).
2. Enter Sleep mode (if desired). Sleep();
3. After exiting Sleep mode (if entered) enable
the FVR (CVRCON2<7> = 1).
4. Wait for the Fixed Voltage Reference to
stabilize (typically 25 us).
while(!CVRCON2bits.FVRST);
5. Re-enable BOR by setting SBOREN
(RCON<6> = 1).
Affected Silicon Revisions
B2 B3 B5 B6
XX
X X