The PIC12F683 parts you have received conform
functionally to the Device Data Sheet (DS41211D),
except for the anomalies described below.
Microchip intends to address all issues listed here in
future revisions of the PIC12F683 silicon.
1. Module: Resets (when WDT times out)
If the OPTION_REG bits, PS<2:0>, are clear,
multiple spurious Resets can occur when the WDT
times out. These Resets can occur even when the
PSA bit is clear, assigning the prescaler to the
Timer0.
Work around
If a CLRWDT instruction is issued before the WDT
times out and before the OPTION register is
modified, this problem is eliminated.
Date Codes that pertain to this issue:
All engineering and production devices.
2. Module: ECCP with Auto-Shutdown
(Silicon Rev. A1 and B1)
The PIC12F683 Rev. A1 silicon for the ECCP
Auto-Shutdown is connected to the CMIF flag. See
Figure 8-2 on the following page.
Rev. A1’s auto-shutdown connection to CMIF
causes the auto-shutdown to incorrectly operate
synchronously. Additionally, reads of CMCON0 will
incorrectly clear an auto-shutdown event.
Work around
Rev. A1 Silicon
1) Poll the COUT bit until it is low.
2) Read CMCON1 to precondition CMIF.
3) If CMCON0 is read while COUT is changing,
repeat steps 1 and 2.
Fix
Rev. B1 Silicon
The Silicon Rev. B1 device (now shipping) has
moved the auto-shutdown connection from CxIF to
CxOUT. This will eliminate the synchronous
shutdown and simplify the use of the comparator
for a shutdown event. Figure 1 shows the function
of auto-shutdown before and after the device
revision.