IMP809, IMP810
Application Information
Negative VCC Transients
The IMP809/810 protect µPs from brownouts and low VCC. Short
duration transients of 100mV amplitude and 20µs or less duration
typically do not cause a false RESET.
Valid Reset with VCC under 1.1V
To ensure logic inputs connected to the IMP809 RESET pin are in resistor at RESET is needed. The value is not critical. A pull-up
a known state when V is under 1.1V, a 100kΩ pull-down resistor to VCC is needed with the IMP810.
CC
V
V
CC
CC
100kΩ
IMP810
IMP809
Power
Power
Supply
Supply
RESET
RESET
100kΩ
GND
GND
809/10_05.eps
809/10_04.eps
Figure 3. RESET Valid with VCC Under 1.1V
Figure 2. RESET Valid with VCC Under 1.1V
Bi-directional Reset Pin Interfacing
The IMP809/810 can interface with µP/µC bi-directional reset
pins by connecting a 4.7kΩ resistor in series with the
IMP809/810 reset output and the µP/µC bi-directional reset pin.
BUF
Buffered
RESET
V
CC
IMP809
Power
Supply
µC or µP
4.7kΩ
RESET
Input
RESET
GND
GND
Bi-directional I/O Pin
(Example: 68HC11)
809/10_06.eps
Figure 4. Bi-directional Reset Pin Interfacing
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