General Description
The MAX6323/MAX6324 microprocessor (µP) supervi-
sory circuits monitor power supplies and µP activity in
digital systems. A watchdog timer looks for activity out-
side an expected window of operation. Six laser-
trimmed reset thresholds are available with ±2.5%
accuracy from +2.32V to +4.63V. Valid RESET output is
guaranteed down to VCC = +1.2V.
The RESET output is either push-pull (MAX6323) or
open-drain (MAX6324). RESET is asserted low when
VCC falls below the reset threshold, or when the manual
reset input (MR) is asserted low. RESET remains assert-
ed for at least 100ms after VCC rises above the reset
threshold and MR is deasserted.
The watchdog pulse output (WDPO) utilizes an open-
drain configuration. It can be triggered either by a fast
timeout fault (watchdog input pulses are too close to
each other) or a slow timeout fault (no watchdog input
pulse is observed within the timeout period). The
watchdog timeout is measured from the last falling
edge of watchdog input (WDI) with a minimum pulse
width of 300ns. WDPO is asserted for 1ms when a fault
is observed. Eight laser-trimmed timeout periods are
available.
The MAX6323/MAX6324 are offered in a 6-pin SOT23
package and operate over the extended temperature
range (-40°C to +125°C).
Applications
Automotive
Industrial
Medical
Embedded Control Systems
Features
oMin/Max (Windowed) Watchdog,
8 Factory-Trimmed Timing Options
oPulsed Open-Drain, Active-Low Watchdog Output
oPower-On Reset
oPrecision Monitoring of +2.5V, +3.0V, +3.3V,
and +5.0V Power Supplies
oOpen-Drain or Push-Pull RESET Outputs
oLow-Power Operation (23µA typ)
oDebounced Manual Reset Input
oGuaranteed Reset Valid to VCC = +1.2V
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
________________________________________________________________
Maxim Integrated Products
1
GND
VCC
WDI
16
5
MAX6323
MAX6324
SOT23
TOP VIEW
2
34
RESET
MR
WDPO
19-1838; Rev 6; 1/11
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
*These devices are factory trimmed to one of eight watchdog-
timeout windows and one of six reset voltage thresholds. Insert
the letter corresponding to the desired watchdog-timeout window
(A, B, C, D, E, F, G, or H) into the blank following the number
6323 or 6324 (see Watchdog Timeout table). Insert the two-digit
code (46, 44, 31, 29, 26, or 23) after the letters UT for the desired
nominal reset threshold (see Reset Threshold Range table at end
of data sheet).
/V denotes an automotive qualified part.
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing “-T” with “+T” when ordering.
Note: There are eight standard versions of each device available
(see Standard Versions table). Sample stock is generally held on
standard versions only. Standard versions have an order incre-
ment requirement of 2500 pieces. Nonstandard versions have an
order increment requirement of 10,000 pieces. Contact factory for
availability of nonstandard versions.
Pin Configuration
Ordering Information
Typical Operating Circuit appears at end of data sheet.
WATCHDOG TIMEOUT*
SUFFIX
A
B
C
D
E
F
G
H719
39
23
15
15
15
15
1.5
MAX
FAST
UNITS
ms
ms
ms
ms
ms
ms
ms
ms
SLOW
MIN UNITS
ms
10
100
300
10
60 s
ms
47
82
1.3 s
*
See Figure 1 for operation.
Watchdog Timeout
PART TEMP
RANGE
PIN-
PACKAGE
RESET
OUTPUT
MAX6323_UT_ _-T -40°C to +125°C 6 SOT23 Push-Pull
Ordering Information continued at end of data sheet.
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC = full range, TA= -40°C to +125°C, unless otherwise noted. Typical values are at VCC = 3V, TA= +25°C.) (Note 1)
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 +6.0V
MR, RESET (MAX6323), WDI................-0.3V to (VCC + 0.3V)
WDPO, RESET (MAX6324) ..............................-0.3V to +6.0V
Input Current, VCC, WDI, MR ..............................................20mA
Output Current, RESET, WDPO ..........................................20mA
Rate of Rise, VCC ............................................................100V/µs
Continuous Power Dissipation (TA= +70°C)
6-Pin SOT23 (derate 8.7mW/°C above +70°C)..........696mW
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow)
Lead(Pb)-Free ............................................................+260°C
Containing Lead.........................................................+240°C
PARAMETER SYMBOL MIN TYP MAX UNITS
4.25 4.38 4.50
4.50 4.63 4.75
Supply Current ICC 27 57 µA
Operating Voltage Range 1.2 5.5VCC V
VCC = 5.5V
VCC = 2.5V or 3.3V 23 45
µA1
VRESET = VWDPO = +5.5V, RESET, WDPO
deasserted
ILKG
WDPO, RESET Output Leakage
V
VCC - 1.5
ISOURCE = 800µA, VCC = 4.75V, RESET
deasserted, (MAX632_ _UT44, MAX632_ _UT46)
VOH
RESET Output Voltage
(MAX6323)
0.8 x VCC
ISOURCE = 500µA, VCC = 3.15V, RESET
deasserted (MAX632_ _UT23, MAX632_ _UT26,
MAX632_ _UT29, MAX632_ _UT31)
V
0.4
ISINK = 100µA, VCC > 1.2V, RESET asserted
VOL
WDPO, RESET Output Voltage
0.4
ISINK = 3.2mA, VCC = 4.25V (MAX632_ _UT44,
MAX632_ _UT46)
0.4
ISINK = 1.2mA, VCC = 2.25V (MAX632_ _UT23,
MAX632_ _UT26, MAX632_ _UT29,
MAX632_ _UT31)
µs2010mV/ms, VTH +100mV to VTH - 100mV
VCC to RESET Delay
ms100 180 280
RESET deasserted
tRP
Reset Timeout Delay
V
2.25 2.32 2.38
CONDITIONS
MAX632_ _UT23
VTH
Reset Threshold Voltage
MAX632_ _UT44
MAX632_ _UT46
No load, RESET
deasserted
2.55 2.63 2.70MAX632_ _UT26
2.85 2.93 3.00MAX632_ _UT29
3.00 3.08 3.15MAX632_ _UT31
MR Input Voltage
MR Minimum Pulse Width
MR Glitch Immunity
MR to Reset Delay
MR Pullup Resistance
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
_______________________________________________________________________________________ 3
CONDITIONS UNITSMIN TYP MAXSYMBOLPARAMETER
ELECTRICAL CHARACTERISTICS (continued)
(VCC = full range, TA= -40°C to +125°C, unless otherwise noted. Typical values are at VCC = 3V, TA= +25°C.) (Note 1)
Note 1: Devices are tested at TA= +25°C and guaranteed by design for TA= TMIN to TMAX, as specified.
Note 2: WDPO will pulse low if a falling edge is detected on WDI before this timeout period expires.
Note 3: To avoid a potential fake fault, the first WDI pulse after the rising edge of RESET or WDPO will not create a fast watchdog
timeout fault.
Note 4: WDPO will pulse low if no falling edge is detected on WDI after this timeout period expires.
MAX632_AUT_ _ 1 1.5
MAX632_BUT_ _ 10 15
MAX632_CUT_ _ 10 15
MAX632_DUT_ _ 10 15
MAX632_EUT_ _ 10 15
MAX632_FUT_ _ 17 23
MAX632_GUT_ _ 29 39
Watchdog Timeout (Fast)
(Notes 2, 3)
MAX632_HUT_ _ 543 719
mstWD1
MAX632_AUT_ _ 10 15
MAX632_BUT_ _ 100 150
MAX632_CUT_ _ 300 450
ms
MAX632_DUT_ _ 10 15
MAX632_EUT_ _ 60 90 s
MAX632_FUT_ _ 47 63
MAX632_GUT_ _ 82 108 ms
tWD2
MAX632_HUT_ _ 1.3 1.8 s
Watchdog Timeout (Slow)
(Note 4)
300 ns
WDI Glitch Immunity VCC = 5.5V 100 ns
VIH 0.75 x VCC
WDI Input Voltage VIL 0.8 V
VWDI = 0V -1.5 -1
WDI Input Current VWDI = VCC 1 1.5 µA
VIL = 0.8V, VIH = 0.75V x VCC 0.5 1 3 ms
VIH 0.7 x VCC
VIL 0.3 x VCC
V
1µs
VCC = 2.5V 100 ns
VCC = 2.5V 120 ns
50 85 kΩ
Minimum Watchdog Input
Pulse Width
WATCHDOG INPUT AND OUTPUT
MANUAL RESET INPUT
WDPO Pulse Width
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
4 _______________________________________________________________________________________
0
30
35
40
25
20
15
10
5
-40 200-20 40 60 80
MAX6323/24-01
TEMPERATURE (°C)
SUPPLY CURRENT vs. TEMPERATURE
SUPPLY CURRENT (µA)
VCC = 5.5V
VCC = 3.3V
VCC = 1.0V
0
30
20
5
-40 200-20 40 60 80
MAX6323/24-02
TEMPERATURE (°C)
POWER-DOWN RESET DELAY (µs)
POWER-DOWN RESET DELAY
vs. TEMPERATURE
VOD = 20mV
VOD = 100mV
25
15
10
0.9985
0.9990
0.9995
1.0000
1.0005
-40 200-20 40 60 80
MAX6323/24-04
TEMPERATURE (°C)
RESET THRESHOLD
NORMALIZED RESET THRESHOLD
vs. TEMPERATURE
0.9980 0.994
1.004
1.006
1.008
-40 200-20 40 60 80
MAX6323/24-05
TEMPERATURE (°C)
POWER-UP RESET TIMEOUT
NORMALIZED POWER-UP RESET TIMEOUT
vs. TEMPERATURE
1.002
1.000
0.998
0.996
0.992
1.004
1.002
1.000
0.998
1.006
1.008
-40 200-20 40 60 80
MAX6323/24-06
TEMPERATURE (°C)
NORMALIZED WATCHDOG TIMEOUT
PERIOD (FAST) vs. TEMPERATURE
NORMALIZED WATCHDOG TIMEOUT PERIOD (FAST)
0.996
0.994
0.995
1.000
1.001
0.999
0.997
0.998
0.996
1.002
1.003
-40 200-20 40 60 80
MAX6323/24-07
TEMPERATURE (°C)
NORMALIZED WATCHDOG TIMEOUT
PERIOD (SLOW) vs. TEMPERATURE
NORMALIZED WATCHDOG TIMEOUT PERIOD (SLOW)
0.992
1.004
1.002
1.000
1.006
1.008
-40 200-20 40 60 80
MAX6323/24-08
TEMPERATURE (°C)
NORMALIZED WATCHDOG OUTPUT PULSE WIDTH (µs)
NORMALIZED WATCHDOG OUTPUT
PULSE WIDTH vs. TEMPERATURE
0.998
0.996
0.994
VOD = VTH - VCC
400
0
1 100 1000
MAXIMUM TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
100
50
150
200
250
300
350
MAX6323/24-09
RESET COMPARATOR OVERDRIVE (mV)
MAXIMUM TRANSIENT DURATION (µs)
10
MAX632_AUT23
RESET ASSERTED
ABOVE THIS LINE
Typical Operating Characteristics
(VCC = full range, TA= +25°C, unless otherwise noted.)
40
120
100
80
60
140
160
-40 200-20 40 60 80
MAX6323/24-03
TEMPERATURE (°C)
MR TO RESET DELAY (ns)
MR TO RESET DELAY
vs. TEMPERATURE
20
0
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
_______________________________________________________________________________________
5
500µs/div
MAX6323/24-10
WDI 2V/div
2V/div
WDPO
FAST WATCHDOG TIMEOUT PERIOD
MAX6323AUT23
5ms/div
MAX6323/24-11
WDI 2V/div
2V/div
WDPO
SLOW WATCHDOG TIMEOUT PERIOD
MAX6323AUT23
Typical Operating Characteristics (continued)
(VCC = full range, TA= +25°C, unless otherwise noted.)
Pin Description
Active-Low. Reset is asserted when VCC drops below VTH and remains asserted until VCC rises above VTH
for the duration of the reset timeout period. The MAX6323 has a push-pull output and the MAX6324 has an
open-drain output. Connect a pullup resistor from RESET to any supply voltage up to +6V.
Watchdog Pulse Output. The open-drain WDPO output is pulsed low for 1ms (typ) upon detection of a fast
or slow watchdog fault. WDPO is only active when RESET is high.
WDPO
5
RESET
6
Supply Voltage for the Device. Input for VCC reset monitor. For noisy systems, bypass VCC with a 500pF
(min) capacitor.
VCC
4
Watchdog Input. The internal watchdog timer clears to zero on the falling edge of WDI or when RESET goes
high. If WDI sees another falling edge within the factory-trimmed watchdog window, WDPO will remain
unasserted. Transitions outside this window, either faster or slower, will cause WDPO to pulse low for 1ms
(typ).
WDI3
PIN
GroundGND2
Active-Low, Manual Reset Input. When MR is asserted low, RESET is asserted low, the internal watchdog
timer is reset to zero, and WDPO is reset to high impedance (open drain). After the rising edge of MR,
RESET is asserted for at least 100ms. Leave MR unconnected or connect to VCC if unused.
MR
1
FUNCTIONNAME
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
6 _______________________________________________________________________________________
Detailed Description
The MAX6323/MAX6324 µP supervisory circuits main-
tain system integrity by alerting the µP to fault condi-
tions. In addition to a standard VCC monitor (for
power-on reset, brownout detect, and power-down
reset), the devices include a sophisticated watchdog
timer that detects when the processor is running out-
side an expected window of operation for a specific
application. The watchdog signals a fault when the
input pulses arrive too early (faster than the selected
tWD1 timeout period) or too late (slower than the select-
ed tWD2 timeout period) (Figure 1). Incorrect timing can
lead to poor or dangerous system performance in tight-
ly controlled operating environments. Incorrect timing
could be the result of improper µP clocking or code
execution errors. If a timing error occurs, the
MAX6323/MAX6324 issue a watchdog pulse output,
independent from the reset output, indicating that sys-
tem maintenance may be required.
Watchdog Function
A pulse on the watchdog output WDPO can be trig-
gered by a fast fault or a slow fault. If the watchdog
input (WDI) has two falling edges too close to each
other (faster than tWD1) (Figure 2) or falling edges that
are too far apart (slower than tWD2) (Figure 3), WDPO is
pulsed low. Normal watchdog operation is displayed in
Figure 4 (WDPO is not asserted). The internal watch-
dog timer is cleared when a WDI falling edge is detect-
ed within the valid watchdog window or when the
device’s RESET or WDPO outputs are deasserted. All
WDI input pulses are ignored while either RESET or
WDPO is asserted. Figure 1 identifies the input timing
regions where WDPO fault outputs will be observed
with respect to tWD1 and tWD2. After RESET or WDPO
deasserts, the first WDI falling edge is ignored for the
fast fault condition (Figure 2).
Upon detecting a watchdog fault, the WDPO output will
pulse low for 1ms. WDPO is an open-drain output.
Connect a pullup resistor on WDPO to any supply up to
+6V.
VCC Reset
The MAX6323/MAX6324 also include a standard VCC
reset monitor to ensure that the µP is started in a known
state and to prevent code execution errors during
power-up, power-down, or brownout conditions.
RESET is asserted whenever the VCC supply voltage
*UNDETERMINED STATES MAY OR MAY NOT GENERATE A FAULT CONDITION.
POSSIBLE STATES
GUARANTEED TO
ASSERT WDPO
GUARANTEED TO
ASSERT WDPO
GUARANTEED NOT TO
ASSERT WDPO
FAST FAULTCONDITION 1
SLOW FAULTCONDITION 3
NORMAL OPERATIONCONDITION 2
tWD1 (min)
)
tWD1 (max) tWD2 (min) tWD2 (max)
*UNDETERMINED *UNDETERMINED
Figure 1. Detailed Watchdog Input Timing Relationship
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
_______________________________________________________________________________________ 7
RESET
WDPO
WDI
FAST FAULT
tWDI < tWD1 (min)
Figure 2. Fast Fault Timing
RESET
WDPO
WDI
SLOW FAULT
tWDI < tWD2 (max)
Figure 3. Slow Fault Timing
RESET
WDPO
WDI
NORMAL OPERATION (NO PULSING, OUTPUT STAYS HIGH)
tWD1 (max) < tWDI < tWD2 (min)
H
L
Figure 4. Normal Operation, WDPO Not Asserted
MAX6323/MAX6324
falls below the preset threshold or when the manual
reset input (MR) is asserted. The RESET output remains
asserted for at least 100ms after VCC has risen above
the reset threshold and MR is deasserted (Figure 5).
For noisy environments, bybass VCC with a 500pF (min)
capacitor to ensure correct operation.
The MAX6323 has a push-pull output stage, and the
MAX6324 utilizes an open-drain output. Connect a pull-
up resistor on the RESET output of the MAX6324 to any
supply up to +6V. Select a resistor value large enough
to register a logic low (see
Electrical Characteristics
)
and small enough to register a logic high while supply-
ing all input leakage currents and leakage paths con-
nected to the RESET line. A 10kΩpullup is sufficient in
most applications.
Manual Reset Input
Many µP-based products require manual reset capabil-
ity to allow an operator or external logic circuitry to initi-
ate a reset. The manual reset input (MR) can connect
directly to a switch without an external pullup resistor or
debouncing network. MR is internally pulled up to VCC
and, therefore, can be left unconnected if unused. MR
is designed to reject fast, negative-going transients
(typically 100ns pulses), and it must be held low for a
minimum of 1µs to assert the reset output (Figure 5). A
0.1µF capacitor from MR to ground provides additional
noise immunity. After MR transitions from low to high,
reset will remain asserted for the duration of the reset
timeout period, at least 100ms.
Applications Information
Negative-Going VCC Transients
The MAX6323/MAX6324 are relatively immune to short-
duration negative-going VCC transients (glitches),
which usually do not require the entire system to shut
down. Typically, 200ns large-amplitude pulses (from
ground to VCC) on the supply will not cause a reset.
Lower amplitude pulses result in greater immunity.
Typically, a VCC transient that falls 100mV below the
reset threshold and lasts less than 20µs will not trigger
a reset (see
Typical Operating Characteristics
). An
optional 0.1µF bypass capacitor mounted close to VCC
provides additional transient immunity.
Ensuring a Valid Reset Output
Down to VCC = 0V
When VCC falls below +1.2V, the MAX6323 RESET out-
put no longer sinks current; it becomes an open circuit.
Therefore, high-impedance CMOS logic inputs con-
nected to RESET can drift to undetermined voltages.
This does not present a problem in most applications,
since most µPs and other circuitry are inoperative with
VCC below +1.2V. However, in applications where
RESET must be valid down to 0, adding a pulldown
resistor to RESET causes any stray leakage currents to
flow to ground, holding RESET low (Figure 6). R1’s
value is not critical; 100kΩis large enough not to load
RESET and small enough to pull RESET to ground. This
scheme does not work with the open-drain output of the
MAX6324.
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
8 _______________________________________________________________________________________
MR
RESET
VCC
VTH
100ms (min)
120ns (typ) 20µs (typ)
1µs (min)
100ms (min)
Figure 5. RESET Timing Relationship
Interfacing to µPs with
Bidirectional Reset Pins
Since the RESET output on the MAX6324 is open-drain,
this device easily interfaces with µPs that have bidirec-
tional reset pins, such as the Motorola 68HC11.
Connecting the µP supervisor’s RESET output directly
to the microcontroller’s (µC’s) RESET pin with a single
pullup resistor allows either device to assert reset
(Figure 7).
MAX6324 Open-Drain
RESET
Output
Allows Use with Multiple Supplies
Generally, the pullup resistor connected to the
MAX6324 will connect to the supply voltage that is
being monitored at the IC’s VCC pin. However, some
systems may use the open-drain output to level-shift
from the monitored supply to reset circuitry powered by
some other supply (Figure 8). Keep in mind that as the
MAX6324’s VCC decreases below +1.2V, so does the
IC’s ability to sink current at RESET. Also, with any pull-
up resistor, RESET will be pulled high as VCC decays
toward 0. The voltage where this occurs depends on
the pullup resistor value and the voltage to which it is
connected.
Watchdog Software Considerations
To help the watchdog timer monitor software execution
more closely, set and reset the watchdog input at dif-
ferent points in the program, rather than “pulsing” the
watchdog input high-low-high or low-high-low. This
technique avoids a “stuck” loop in which the watchdog
time would continue to be reset within the loop, keeping
the watchdog from timing out.
Figure 9 shows an example of a flow diagram where
the I/O driving the watchdog input is set high at the
beginning of the program, set low at the beginning of
every subroutine or loop, then set high again when the
program returns to the beginning. If the program should
“hang” in any subroutine, the problem would be quickly
corrected, since the I/O is continually set low and the
watchdog time is allowed to time out, causing a reset or
interrupt to be issued.
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
_______________________________________________________________________________________ 9
MAX6323
GND
VCC
VCC
RESET
R1
100k
Figure 6. RESET Valid to VCC = Ground Circuit
MAX6324
GND GND
VCC
VCC VCC
µP
RESET RESET
INPUT
Figure 7. Interfacing to µPs with Bidirectional Reset Pins
MAX6324
GND GND
VCC
+3.3V +5.0V
VCC
5V SYSTEM
RESET RESET
INPUT
RPULLUP
Figure 8. MAX6324 Open-Drain RESET Output Allows Use with
Multiple Supplies
WDPO
to
MR
Loopback
An error detected by the watchdog often indicates that
a problem has occurred in the µP code execution. This
could be a stalled instruction or a loop from which the
processor cannot free itself. If the µP will still respond
to a nonmaskable input (NMI), the processor can be
redirected to the proper code sequence by connecting
the WDPO output to an NMI input. Internal RAM data
should not be lost, but it may have been contaminated
by the same error that caused the watchdog to time
out.
If the processor will not recognize NMI inputs, or if the
internal data is considered potentially corrupted when
a watchdog error occurs, the processor should be
restarted with a reset function. To obtain proper reset
timing characteristics, the WDPO output should be
connected to the MR input, and the RESET output
should drive the µP RESET input (Figure 10). The short
1ms WDPO pulse output will assert the manual reset
input and force the RESET output to assert for the full
reset timeout period (100ms min). All internal RAM data
is lost during the reset period, but the processor is
guaranteed to begin in the proper operating state.
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
10 ______________________________________________________________________________________
START
SET WDI
LOW
SUBROUTINE OR
PROGRAM LOOP
SET WDI HIGH
RETURN
END
Figure 9. Watchdog Flow Diagram
MAX6323
MAX6324
RESET
WDPO
µP
RESET
*MAX6324 ONLY
MR WDI I/O
GND
VCC VCC
VCC
*RPULLUP
500pF
Figure 10. WDPO to MR Loopback Circuit
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
______________________________________________________________________________________ 11
Chip Information
TRANSISTOR COUNT: 1371
PROCESS: BiCMOS
SUFFIX
46
44
31
29
26
23
MIN MAX UNITS
V
4.75
4.50
3.15
3.00
2.70
2.382.32
2.63
2.93
3.08
4.38
4.63
TYP
4.50
4.25
3.00
2.85
2.55
2.25
MAX6323AUT29 MAX6324AUT29
MAX6323AUT46 MAX6324AUT46
MAX6323CUT29 MAX6324BUT29
MAX6323CUT46 MAX6324BUT46
MAX6323DUT29 MAX6324EUT29
MAX6323DUT46 MAX6324EUT46
MAX6323HUT29 MAX6324HUT29
MAX6323HUT46 MAX6324HUT46
Reset Threshold Range
(-40°C to +125°C)
Standard Versions
Ordering Information (continued)
PART TEMP
RANGE
PIN-
PACKAGE
RESET
OUTPUT
MAX6324_UT_ _-T -40°C to +125°C 6 SOT23 Open
Drain
MAX6324_UT_ _/V-T -40°C to +125°C 6 SOT23 Open
Drain
M AX 6324_U T_ _/V + T -40°C to +125°C 6 SOT23 Open
Drain
*These devices are factory trimmed to one of eight watchdog-
timeout windows and one of six reset voltage thresholds. Insert
the letter corresponding to the desired watchdog-timeout window
(A, B, C, D, E, F, G, or H) into the blank following the number
6323 or 6324 (see Watchdog Timeout table). Insert the two-digit
code (46, 44, 31, 29, 26, or 23) after the letters UT for the desired
nominal reset threshold (see Reset Threshold Range table at end
of data sheet).
/V denotes an automotive qualified part.
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing “-T” with “+T” when ordering.
Note: There are eight standard versions of each device available
(see Standard Versions table). Sample stock is generally held on
standard versions only. Standard versions have an order incre-
ment requirement of 2500 pieces. Nonstandard versions have an
order increment requirement of 10,000 pieces. Contact factory for
availability of nonstandard versions.
MAX6323/MAX6324
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
12 ______________________________________________________________________________________
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the
package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the
package regardless of RoHS status.
MAX6323
MAX6324
RESET
WDPO NMI
µP
RESET
*MAX6324 ONLY
MR WDI I/O
GND
VCC VCC
VCC
*RPULLUP
500pF
Typical Operating Circuit
PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND
PATTERN NO.
6 SOT23 U6-1 21-0058 90-0175
µP Supervisory Circuits with Windowed
(Min/Max) Watchdog and Manual Reset
MAX6323/MAX6324
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________
13
© 2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
0 10/00 Initial release —
5 5/10 Updated the Ordering Information and Absolute Maximum Ratings. 1, 2, 10
6 1/11 Corrected placement of /V in the Ordering Information section 11
