Datasheet

STM809/810/811/812 Description
Doc ID 9873 Rev 5 5/21
1 Description
The STM809/810/811/812 microprocessor reset circuits are low-power supervisory devices
used to monitor power supplies. They perform a single function: asserting a reset signal
whenever the V
CC
supply voltage drops below a preset value and keeping it asserted until
V
CC
has risen above the preset threshold for a minimum period of time (t
rec
). The
STM811/812 also provide a push-button reset input (MR
).
Figure 1. Logic diagram (STM809/810)
1. For STM810
Figure 2. Logic diagram (STM811/812)
1. For STM812
Table 2. Signal names
V
SS
Ground
RST Active-low reset output
RST
(1)
1. STM810/812 only
Active-high reset output
V
CC
Supply voltage
MR
(2)
2. STM811/812 only
Manual reset input
AI07832
V
CC
STM809/810
V
SS
RST (RST)
(1)
AI07831
V
CC
STM811/812
V
SS
RST (RST)
(1)
MR