19-0412; Rev 1; 12/05
±1% Accuracy, Low-Power, +3V and +5V
µP Supervisory Circuits
____________________________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
the correct state for VCC down to 1V. The reset comparator is designed to ignore fast transients on VCC.
Reset thresholds are available for operation with a variety 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 packages. See the Selector Table for a review of features.
_____________________Selector Table
RESET Output
FEATURE
MAX814
✔
RESET Output
✔
Manual Reset
✔
✔
✔
Power-Fail Monitor
K, L, N, T
✔
K, L, N, T
✔
Adjustable
✔
Low-Line Detector
✔
VCC Reset Voltage
MAX815
✔
MAX816
✔
♦ ±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
♦ 200ms Reset Time Delay
♦ Active-Low RESET Output
Active-High RESET Output (MAX814/MAX816)
♦ 75µA Max Supply Current
♦ Guaranteed RESET Valid to VCC = 1V
♦ Manual Reset Input
♦ ±2% Power-Fail Comparator
♦ Independent Watchdog with 1.56sec Timeout
(MAX815)
♦ Power-Supply Glitch Immunity
♦ 8-Pin SO and DIP Packages
✔
______________Ordering Information
PART*
MAX814_CPA
✔
Watchdog Circuit
________________________Applications
Medical Equipment
Controllers
Intelligent Instruments
Critical µP Power Monitoring
Portable/Battery-Powered Equipment
Set-Top Boxes
TEMP RANGE
0°C to +70°C
PIN-PACKAGE
8 PDIP
*The MAX814/MAX815 offer a choice of reset threshold voltages.
From the Reset Trip Threshold table, select the suffix corresponding 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.
Ordering Information continued at end of data sheet.
Reset Trip Thresholds table appears at end of data sheet.
__________________________________________________________Pin Configurations
TOP VIEW
MR 1
8
RESET
MR 1
7
RESET
VCC 2
GND 3
6
LOW LINE
PFI 4
5
PFO
VCC 2
MAX814
DIP/SO
8
WDO
MR 1
7
RESET
VCC 2
GND 3
6
WDI
PFI 4
5
PFO
MAX815
DIP/SO
8
RESET
7
RESET
GND 3
6
RESET IN
PFI 4
5
PFO
MAX816
DIP/SO
________________________________________________________________ Maxim Integrated Products
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.
1
MAX814/MAX815/MAX816
_______________General Description
