19-0412; Rev 1; 12/05
1ꢀ Accuracꢁ, Low-Power, +3V and +5V
µP Supervisorꢁ Circuits
_______________General Description
____________________________Features
The MAX814/MAX815/MAX816 are high-accuracy
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
♦ Active-Low RESET Output
Active-High RESET Output (MAX814/MAX816)
♦ 75µA Max Supply Current
Reset thresholds are available for operation with a vari-
ety of 3V and 5V supply voltages.
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 pack-
ages. See the Selector Table for a review of features.
♦ Guaranteed RESET Valid to V
♦ Manual Reset Input
= 1V
CC
♦
2% Power-Fail Comparator
♦ Independent Watchdog with 1.56sec Timeout
(MAX815)
_____________________Selector Table
♦ Power-Supply Glitch Immunity
♦ 8-Pin SO and DIP Packages
FEATURE
RESET Output
RESET Output
Manual Reset
MAX814
MAX815
MAX816
✔
✔
✔
✔
✔
✔
✔
✔
______________Ordering Information
V
Reset Voltage
K, L, N, T
K, L, N, T Adjustable
CC
PART*
TEMP RANGE
PIN-PACKAGE
✔
✔
✔
Power-Fail Monitor
Low-Line Detector
Watchdog Circuit
MAX814_CPA
0°C to +70°C
8 PDIP
✔
*The MAX814/MAX815 offer a choice of reset threshold voltages.
From the Reset Trip Threshold table, select the suffix corre-
sponding to the desired threshold and insert it into the blank to
complete the part number.
Devices are available in both leaded and lead-free packaging.
Specify lead free by adding the + symbol at the end of the part
number when ordering.
✔
________________________Applications
Medical Equipment
Controllers
Intelligent Instruments
Critical µP Power Monitoring
Portable/Battery-Powered Equipment
Set-Top Boxes
Ordering Information continued at end of data sheet.
Reset Trip Thresholds table appears at end of data sheet.
__________________________________________________________Pin Configurations
TOP VIEW
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
RESET
RESET
LOW LINE
PFO
WDO
RESET
WDI
RESET
RESET
RESET IN
PFO
MR
MR
MR
V
V
V
CC
CC
CC
MAX814
MAX815
MAX816
GND
GND
GND
PFI
PFI
PFO
PFI
DIP/SO
DIP/SO
DIP/SO
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.