19-0412; Rev 0; 6/95
±1 % Ac c u ra c y, Lo w -P o w e r, +3 V a n d +5 V
µP S u p e rvis o ry Circ u it s
45/MAX816
_______________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
The MAX814/MAX815/MAX816 a re hig h-a c c ura c y
microprocessor (µP) supervisory circuits that provide
power-on reset, watchdog, and power-fail functions.
They eliminate manual trimming and improve reliability
in critical applications needing high-accuracy reset
thresholds. The RESET output is guaranteed to be in
♦ ±1% Worst-Case Reset Threshold Accuracy
♦ 4.8V, 4.7V, 4.55V, 3.03V, or Adjustable Reset
Thresholds
♦ ±1% Low-Line Threshold Accuracy (MAX814)
60mV Above Reset Threshold
the correct state for V
down to 1V. The reset com-
CC
♦ 200ms Reset Time Delay
parator is designed to ignore fast transients on V
.
CC
Reset thresholds are available for operation with a vari-
ety of 3V and 5V supply voltages.
♦ Active-Low RESET Output
Active-High RESET Output (MAX814/MAX816)
A 75µA maximum supply current makes the MAX814/
MAX815/MAX816 ideal for use in portable equipment.
All three devices are available in 8-pin DIP and SO
packages. See the Selector Table below for a review of
features.
♦ 75µA Max Supply Current
♦ Guaranteed RESET Valid to V
♦ Manual Reset Input
= 1V
CC
♦ ±2% Power-Fail Comparator
_____________________S e le c t o r Ta b le
♦ Independent Watchdog with 1.56sec Timeout
(MAX815)
FEATURE
RESET Output
RESET Output
Manual Reset
MAX814
MAX815
MAX816
✔
✔
✔
✔
✔
✔
✔
♦ Power-Supply Glitch Immunity
♦ 8-Pin SO and DIP Packages
✔
V
Reset Voltage
K, L, N, T
K, L, N, T Adjustable
CC
_____________Re s e t Trip Th re s h o ld s
✔
✔
✔
✔
Power-Fail Monitor
Low-Line Detector
Watchdog Circuit
MAX814/MAX815
RESET TRIP THRESHOLD
SUFFIX
✔
MIN (V)
4.75
MAX (V)
4.85
K
L
________________________Ap p lic a t io n s
Medical Equipment
4.65
4.75
N
T
4.50
4.60
Controllers
Intelligent Instruments
Critical µP Power Monitoring
Portable/Battery-Powered Equipment
Set-Top Boxes
3.00
3.06
MAX816
—
Adjustable
Ordering Information appears at end of data sheet.
__________________________________________________________P in Co n fig u ra t io n s
TOP VIEW
1
2
3
4
8
7
6
5
RESET
RESET
LOW LINE
PFO
1
2
3
4
8
7
6
5
WDO
RESET
WDI
1
2
3
4
8
7
6
5
RESET
RESET
RESET IN
PFO
MR
MR
MR
V
CC
V
CC
V
CC
MAX814
MAX815
MAX816
GND
GND
GND
PFI
PFI
PFO
PFI
DIP/SO
DIP/SO
DIP/SO
________________________________________________________________ Maxim Integrated Products
1
Ca ll t o ll fre e 1 -8 0 0 -9 9 8 -8 8 0 0 fo r fre e s a m p le s o r lit e ra t u re .