Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

ADM809 Datasheet(PDF) 5 Page - Analog Devices

Part No. ADM809
Description  Microprocessor Supervisory Circuit in 3-Pin SOT-23
Download  6 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  AD [Analog Devices]
Homepage  http://www.analog.com
Logo 

ADM809 Datasheet(HTML) 5 Page - Analog Devices

   
Zoom Inzoom in Zoom Outzoom out
 5 / 6 page
background image
ADM809/ADM810
–5–
REV. 0
INTERFACING TO OTHER DEVICES OUTPUT
The ADM809/ADM810 Series is designed to integrate with as
many devices as possible and therefore has a standard output
dependant on VCC. This enables the part to be used in both 3 V
and 5 V or any nominal voltage within the minimum and maxi-
mum specifications for VCC. Because of this design approach,
interfacing this device to other devices is simplified.
ENSURING A VALID RESET OUTPUT DOWN TO VCC = 0 V
When VCC falls below 0.8 V, ADM809’s RESET no longer
sinks current. A high impedance CMOS logic input connected
to RESET may, therefore, drift to undetermined logic levels. To
eliminate this problem a 100 k
Ω resistor should be connected
from RESET to ground.
VCC
VCC
GND
RESET
ADM809
Figure 10. Ensuring a Valid RESET Output Down to
VCC = 0 V
THE BENEFITS OF A VERY ACCURATE RESET
THRESHOLD
In other microprocessor supervisory circuits, tolerances in sup-
ply voltages lead to an overall increase in RESET tolerance
levels due to the deterioration of the microprocessor RESET
circuit’s power supply. The possibility of a malfunction during
a power failure is greatly reduced because the ADM809 and
ADM810 series can operate effectively even when there are
large degradations of the supply voltages. Another advantage of
the ADM809 and ADM810 series is its very accurate internal
voltage reference circuit. These benefits combine to produce an
exceptionally reliable Voltage Monitor Circuit.
INTERFACING TO MICROPROCESSORS WITH
MULTIPLE INTERRUPTS
In a number of cases it is necessary to interface many interrupts
from different devices (i.e., thermal, attitude and velocity sen-
sors). The ADM809 and ADM810 can easily be integrated into
existing interrupt-handling circuits (Figure 11) or used as a
stand-alone device.
PRIORITY ENCODER
74LS147
4 LINE BCD
TO
µP
VCC
ADM809
GND
RESET
OTHER SENSING
DEVICES
VCC
Figure 11. Interfacing to
µPs with Multiple Interrupts


Html Pages

1  2  3  4  5  6 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn