MAX6369KAT ,Pin-Selectable Watchdog TimersApplicationssignal when a system is operating improperly. During Pin-Selectable Watchdog Timeout P ..
MAX6369KA-T ,Pin-Selectable Watchdog TimersApplicationsMAX6373KA-T -40°C to +85°C 8 SOT23-8 AADGEmbedded Control SystemsMAX6374KA-T -40°C to + ..
MAX636ACPA ,Preset -12V output or adjuistable output with 2 resistors, CMOS switching regulator. Output accuracy 5%.Features
The MAX635/MAX636/MAX637 inverting switching regu- . Preset -5V, -12V, -15V Output Volt ..
MAX636ACSA ,Preset -12V output or adjuistable output with 2 resistors, CMOS switching regulator. Output accuracy 5%.Applications MAX635XMJA -55°C to +125°C 8 CERDIP
. . . . . MAX636XCPA 0°C to +70°C 8 Plastic DIP
..
MAX636ACSA ,Preset -12V output or adjuistable output with 2 resistors, CMOS switching regulator. Output accuracy 5%.19-0918; Re v tk 5/91
[VI llXI/VI
Preset/Adiustable Output CMOS
Inverting Switching Regulato ..
MAX636ACSA+ ,Preset/Adjustable Output CMOS Inverting Switching Regulatorsfeatures such as MAX635XCSA 0 C to +70 C 8 Narrow SO
Itogic-level shutdown, adjustable oscillator ..
MB15U10 ,Dual Serial Input PLL Frequency Synthesizer On-Chip 1.1 GHz PrescalerFUJITSU SEMICONDUCTORDS04-21339-2EDATA SHEETASSPDual Serial Input PLL Frequency SynthesizerOn-Chip ..
MB15U10PFV ,Dual Serial Input PLL Frequency Synthesizer On-Chip 1.1 GHz PrescalerFUJITSU SEMICONDUCTORDS04-21339-2EDATA SHEETASSPDual Serial Input PLL Frequency SynthesizerOn-Chip ..
MB15U36 ,Dual PLL Frequency Synthesizer with On-Chip PrescalerFeatures Very low spurious and phase noise characteristics 18-bit programmable divider:– Binary 7 ..
MB15U36PFV ,Dual PLL Frequency Synthesizer with On-Chip PrescalerFeatures Very low spurious and phase noise characteristics 18-bit programmable divider:– Binary 7 ..
MB2245BB ,16-bit transceivers with direction pins 3-State
MB2245BB ,16-bit transceivers with direction pins 3-State
MAX6369KAT-MAX6369KA-T-MAX6370KA-T-MAX6372KA-T-MAX6373KAT-MAX6373KA-T
Pin-Selectable Watchdog Timers
General DescriptionThe MAX6369–MAX6374 are pin-selectable watchdog
timers that supervise microprocessor (µP) activity and
signal when a system is operating improperly. During
normal operation, the microprocessor should repeated-
ly toggle the watchdog input (WDI) before the selected
watchdog timeout period elapses to demonstrate that
the system is processing code properly. If the µP does
not provide a valid watchdog input transition before the
timeout period expires, the supervisor asserts a watch-
dog (WDO) output to signal that the system is not exe-
cuting the desired instructions within the expected time
frame. The watchdog output pulse can be used to reset
the µP or interrupt the system to warn of processing
errors.
The MAX6369–MAX6374 are flexible watchdog timer
supervisors that can increase system reliability through
notification of code execution errors. The family offers
several pin-selectable watchdog timing options to
match a wide range of system timing applications:Watchdog startup delay: provides an initial delay
before the watchdog timer is started.Watchdog timeout period: normal operating watch-
dog timeout period after the initial startup delay.Watchdog output/timing options: open drain (100ms)
or push-pull (1ms).
The MAX6369–MAX6374 operate over a +2.5V to +5.5V
supply range and are available in miniature 8-pin
SOT23 packages.
________________________ApplicationsEmbedded Control Systems
Industrial Controllers
Critical µP and Microcontroller (µC) Monitoring
Automotive
Telecommunications
Networking
FeaturesPrecision Watchdog Timer for Critical
µP ApplicationsPin-Selectable Watchdog Timeout PeriodsPin-Selectable Watchdog Startup Delay PeriodsAbility to Change Watchdog Timing Characteristics
Without Power CyclingOpen-Drain or Push-Pull Pulsed Active-Low
Watchdog OutputWatchdog Timer Disable Feature+2.5V to +5.5V Operating Voltage 8µA Low Supply Current No External Components RequiredMiniature 8-Pin SOT23 Package
MAX6369–MAX6374
Pin-Selectable Watchdog Timers19-1676; Rev 2; 2/03
Ordering Information
Pin Configuration appears at end of data sheet.
Note:All devices are available in tape-and-reel only. Required
order increment is 2,500 pieces.
Selector Guide
MAX6369–MAX6374
Pin-Selectable Watchdog Timers
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VCC= +2.5V to +5.5V, SET_ = VCCor GND, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C and
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Terminal Voltage (with respect to GND)
VCC.....................................................................-0.3V to +6V
WDI.....................................................................-0.3V to +6V
WDO(Open Drain: MAX6369/71/73).................-0.3V to +6V
WDO(Push-Pull: MAX6370/72/74 .......-0.3V to (VCC+ 0.3V)
SET0, SET1, SET2................................-0.3V to (VCC+ 0.3V)
Maximum Current, Any Pin (input/output)...........................20mA
Continuous Power Dissipation (TA= +70°C)
SOT23-8 (derate 8.75mW/°C above +70°C)...............700mW
Operating Temperature Range...........................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Junction Temperature......................................................+150°C
Lead Temperature (soldering, 10s).................................+300°C
VCCRise or Fall Rate......................................................0.05V/µs
MAX6369–MAX6374
Pin-Selectable Watchdog Timers
ELECTRICAL CHARACTERISTICS (continued)(VCC= +2.5V to +5.5V, SET_ = VCCor GND, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C and
MAX6369–MAX6374
Pin-Selectable Watchdog TimersSUPPLY CURRENT
vs. TEMPERATURE
MAX6369/74-01
TEMPERATURE (°C)
SUPPLY CURRENT (
Typical Operating Characteristics (Circuit of Figure 1, TA= +25°C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS (continued)(VCC= +2.5V to +5.5V, SET_ = VCCor GND, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C and
Note 1:Production tested at TA= +25°C. Guaranteed by design over temperature limits.
Note 2:Guaranteed by design.
Note 3:In this setting the watchdog timer is inactive and startup delay ends when WDI sees its first level transition. See Selecting
Device Timingfor more information.
Note 4:After power-up, or a setting change, there is an internal setup time during which WDI is ignored.
MAX6369–MAX6374
Pin-Selectable Watchdog Timers
Pin Description
Detailed DescriptionThe MAX6369–MAX6374 are flexible watchdog circuits
for monitoring µP activity. During normal operation, the
internal timer is cleared each time the µP toggles the
WDI with a valid logic transition (low to high or high to
low) within the selected timeout period (tWD). The WDO
remains high as long as the input is strobed within the
selected timeout period. If the input is not strobed
before the timeout period expires, the watchdog output
is asserted low for the watchdog output pulse width
(tWDO). The device type and the state of the three logic
control pins (SET0, SET1, and SET2) determine watch-
dog timing characteristics. The three basic timing varia-
tions for the watchdog startup delay and the normal
watchdog timeout period are summarized below (see
Table 1 for the timeout characteristics for all devices in
the family): Watchdog Startup Delay:
Provides an initial delay before the watchdog timer is
started.
Allows time for the µP system to power up and initial-
ize before assuming responsibility for normal watch-
dog timer updates.
Includes several fixed or pin-selectable startup delay
options from 200µs to 60s, and an option to wait for
the first watchdog input transition before starting the
watchdog timer.
MAX6369–MAX6374
Pin-Selectable Watchdog TimersWatchdog Timeout Period:
Normal operating watchdog timeout period after the
initial startup delay.
A watchdog output pulse is asserted if a valid watch-
dog input transition is not received before the timeout
period elapses.
Eight pin-selectable timeout period options for each
device, from 30µs to 60s.
Pin-selectable watchdog timer disable feature.Watchdog Output/Timing Options:
Open drain, active low with 100ms minimum watch-
dog output pulse (MAX6369/MAX6371/MAX6373).
Push-pull, active low with 1ms minimum watchdog
output pulse (MAX6370/MAX6372/MAX6374).
Each device has a watchdog startup delay that is initi-
ated when the supervisor is first powered or after the
user modifies any of the logic control set inputs. The
watchdog timer does not begin to count down until the
Figure 1. Functional Diagram
