MAX690T Datasheet, PDF (1/12 Pages) Maxim Integrated Products – 3.0V/3.3V Microprocessor Supervisory Circuits

19-0243; Rev 1; 9/94
3.0V/3.3V Microprocessor Supervisory Circuits
_______________General Description
These microprocessor (µP) supervisory circuits reduce
the complexity and number of components required for
power-supply monitoring and battery-control functions
in µP systems. They significantly improve system relia-
bility and accuracy compared to separate ICs or
discrete components.
These devices are designed for use in systems powered
by 3.0V or 3.3V supplies. See the selector guide in the
back of this data sheet for similar devices designed for
5V systems. The suffixes denote different reset threshold
voltages: 3.075V (T), 2.925V (S), and 2.625V (R) (see
Reset Threshold section in the Detailed Description). All
these parts are available in 8-pin DIP and SO packages.
Functions offered in this series are as follows:
Part
MAX690 

MAX704 

MAX802 

MAX804

MAX805

MAX806 

 ±4%  ±75mV
 ±4%  ±75mV
 ±2%  ±2%
 ±2%  ±2%
 ±4%  ±75mV
 ±2%  ±2%
________________________Applications
Battery-Powered Computers and Controllers
Embedded Controllers
Intelligent Instruments
Automotive Systems
Critical µP Power Monitoring
Portable Equipment
__________________Pin Configuration
TOP VIEW
VOUT ¹
VCC ²
GND ³
PFI ⁴
MAX690T/S/R
MAX704T/S/R
MAX802T/S/R
MAX804T/S/R
MAX805T/S/R
MAX806T/S/R
DIP/SO
( ) ARE FOR MAX804T/S/R, MAX805T/S/R
< > ARE FOR MAX704T/S/R, MAX806T/S/R
8 _VBATT
7 RESET (RESET)
6 _{WDI <MR>}
5 _PFO
____________________________Features
o ^{–R—E—S—E—T–} and RESET Outputs
o Manual Reset Input
o Precision Supply-Voltage Monitor
o 200ms Reset Time Delay
o Watchdog Timer (1.6sec timeout)
o Battery-Backup Power Switching—
Battery Can Exceed V_CC in Normal Operation
o 40µA V_CC Supply Current
o 1µA Battery Supply Current
o Voltage Monitor for Power-Fail or
Low-Battery Warning
o Guaranteed ^{–R—E—S—E—T–} Assertion to V_CC = 1V
o 8-Pin DIP and SO Packages
______________Ordering Information
PART**
MAX690_CPA
MAX690_CSA
MAX690_C/D
MAX690_EPA
MAX690_ESA
MAX690_MJA
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
PIN-PACKAGE
8 Plastic DIP
8 SO
Dice*
8 Plastic DIP
8 SO
8 CERDIP
Ordering Information continued on last page.
* Contact factory for dice specifications.
** These parts offer a choice of reset threshold voltage. Select
the letter corresponding to the desired nominal reset threshold
voltage (T = 3.075V, S = 2.925V, R = 2.625V) and insert it into
the blank to complete the part number.
_________Typical Operating Circuits
REGULATED +3.3V OR +3.0V
UNREGULATED
DC
0.1µF
R1
3.6V
R2
LITHIUM
BATTERY
V_CC
RESET
(RESET)
PFO
PFI
MAX690T/S/R
MAX802T/S/R
WDI
MAX804T/S/R
MAX805T/S/R
VBATT
V_OUT
GND
0.1µF
0.1µF
( ) ARE FOR MAX804T/S/R, MAX805T/S/R
See last page for MAX704T/S/R, MAX806T/S/R.
VCC _µP
RESET
NMI
I/O LINE GND
BUS
V_CC
CMOS RAM
GND
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