Maxim MAX6358LSUK-T Dual/triple-voltage î¼p supervisory circuit Datasheet

19-1508; Rev 1; 10/99
Dual/Triple-Voltage
µP Supervisory Circuits
The MAX6351 features both 3V and 5V active-low pushpull reset outputs. The MAX6353/MAX6356/MAX6359
offer a 5V active-low push-pull reset. The MAX6354/
MAX6357/MAX6360 offer a 3V active-low push-pull
reset. The MAX6352/MAX6355/MAX6358’s reset is
active-low open-drain.
All of these devices are offered with a wide variety of
voltage threshold levels, as shown in the Voltage
Threshold Levels table below. They are available in 5and 6-pin SOT23 packages and operate over the
extended (-40°C to +85°C) temperature range.
Features
♦ Precision Monitoring of Multiple +2.5V, +3.0V,
+3.3V, and +5V Power-Supply Voltages
♦ Precision Factory-Set Power-Supply
Reset Thresholds
♦ 20µA Supply Current
♦ 100ms min Power-On Reset Pulse Width
♦ Fully Guaranteed Over Temperature
♦ Guaranteed RESET Valid to VCC5 = 1V or
VCC3 = 1V
♦ Power-Supply Transient Immunity
♦ No External Components for Dual-Voltage
Systems
♦ Small 5- and 6-Pin SOT23 Packages
♦ Debounced TTL/CMOS-Compatible
Manual-Reset Input
♦ Watchdog Timer
46.4sec Start-Up Timeout
2.9sec Normal Timeout
♦ Low Cost
Applications
Computers
Controllers
Portable/Battery-Powered
Equipment
Intelligent Instruments
Multivoltage Systems
__________Voltage Threshold Levels
PART NO.
SUFFIX
(_ _)
VCC5 NOMINAL
VOLTAGE
THRESHOLD (V)
VCC3 NOMINAL
VOLTAGE
THRESHOLD (V)
LT
4.63
3.08
LS
4.63
2.93
LR
4.63
2.63
MT
4.38
3.08
MS
4.38
2.93
MR
4.38
2.63
TY
3.08
2.19
SY
2.93
2.19
Note: Standard versions are shown in bold and have a required
order increment of 2500 pieces. Sample stock is generally held on
the standard versions only. The required order increment for nonstandard versions is 10,000 pieces. Contact factory for availability.
Ordering Information
PART*
TEMP. RANGE
PIN-PACKAGE
MAX6351_ _UT-T
-40°C to +85°C
6 SOT23-6
MAX6352_ _UK-T
MAX6353_ _UK-T
MAX6354_ _UK-T
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
5 SOT23-5
5 SOT23-5
5 SOT23-5
MAX6355_ _UT-T
MAX6356_ _UT-T
MAX6357_ _UT-T
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
6 SOT23-6
6 SOT23-6
6 SOT23-6
MAX6358_ _UT-T
MAX6359_ _UT-T
MAX6360_ _UT-T
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
6 SOT23-6
6 SOT23-6
6 SOT23-6
*The _ _ are placeholders for the threshold voltage levels of the
devices. Substitute the part number suffix in the Voltage
Threshold Levels table for the desired voltage level. There are
two standard versions for each of the above part numbers. All
devices are available in tape-and-reel only.
Pin Configurations appear at end of data sheet.
Selector Guide appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
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For small orders, phone 1-800-835-8769.
MAX6351–MAX6360
General Description
The MAX6351–MAX6360 microprocessor (µP) supervisors with multiple reset voltages significantly improve
system reliability and accuracy compared to separate
ICs or discrete components. If any input supply voltage
drops below its associated preset threshold, all reset
outputs are asserted. In addition, the output(s) is valid
as long as either input supply voltage remains greater
than +1.0V.
All devices in this series have an active-low debounced
manual reset input. In addition, the MAX6358/MAX6359/
MAX6360 offer a watchdog timer input with a 46.4sec
start-up timeout period and a 2.9sec timeout period.
The MAX6355/MAX6356/MAX6357 offer an additional
voltage monitor input to monitor a third voltage.
MAX6351–MAX6360
Dual/Triple-Voltage
µP Supervisory Circuits
ABSOLUTE MAXIMUM RATINGS
VCC5, VCC3 to GND .................................................-0.3V to +6V
RST (MAX6352/55/58) ............................................. -0.3V to +6V
RST, MR, WDI, RST5, RSTIN
(MAX6351/53/56/59).............................-0.3V to (VCC5 + 0.3V)
RST, RST3 (MAX6351/54/57/60) .................-3V to (VCC3 + 0.3V)
Input/Output Current, All Pins .............................................20mA
Continuous Power Dissipation (TA = +70°C)
5-Pin SOT23-5 (derate 7.1mW/°C above +70°C) ........571mW
6-Pin SOT23-6 (derate 7.1mW/°C above +70°C) ........571mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
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.
ELECTRICAL CHARACTERISTICS
(VCC3 = VCC5 = +1.2V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Supply Voltage Range (Note 2)
Supply Current
SYMBOL
VCC
ICC5 +
ICC3
CONDITIONS
TA = -40°C to +85°C
1.2
5.5
20
VCC5 = 5.5V, VCC3 = 3.6V, all I/O pins open
VTH5
MAX63_ _T_
MAX63_ _S_
MAX63_ _ _T
MAX63_ _ _S
VTH3
MAX63_ _ _R
MAX63_ _ _Y
Reset Threshold Tempco
TA = +25°C
4.54
TA = -40°C to +85°C
4.5
TA = +25°C
4.3
TA = -40°C to +85°C
4.25
TA = +25°C
3.03
TA = -40°C to +85°C
3.00
TA = +25°C
2.88
TA = -40°C to +85°C
2.85
TA = +25°C
3.03
TA = -40°C to +85°C
3.00
TA = +25°C
2.88
TA = -40°C to +85°C
2.85
TA = +25°C
2.58
TA = -40°C to +85°C
2.55
TA = +25°C
2.16
TA = -40°C to +85°C
2.13
∆VTH/°C
Reset Timeout Period
RESET Output Voltage Low
2
100mV overdrive
tRP
VOL
4.63
50
VCC5 > VTH5(MAX), VCC3 > VTH3(MAX)
100
UNITS
V
µA
4.72
4.75
4.38
4.46
3.08
3.14
4.50
V
3.15
2.93
2.98
3.00
3.08
3.14
3.15
2.93
2.98
2.63
2.68
2.19
2.22
3.00
V
2.70
2.25
20
Reset Threshold Hysteresis
VCC to Reset Delay
MAX
5.5
MAX63_ _M_
VCC3 Threshold (Note 3)
TYP
1.0
MAX63_ _L_
VCC5 Threshold (Note 3)
MIN
TA = 0°C to +70°C
ppm/°C
VTH/500
V
20
µs
180
280
VCC5 or VCC3 ≥ 2.7V, ISINK = 1.2mA
0.3
VCC5 or VCC3 ≥ 4.5V, ISINK = 3.2mA
0.4
VCC5 or VCC3 < 1V, ISINK = 50µA,
TA = 0°C to +70°C
0.3
VCC5 or VCC3 < 1.2V, ISINK = 50µA
0.3
_______________________________________________________________________________________
ms
V
V
Dual/Triple-Voltage
µP Supervisory Circuits
(VCC3 = VCC5 = +1.2V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MAX6351/MAX6353/
MAX6354/MAX6356/
MAX6357/MAX6359/
MAX6360
(_Y versions only),
VCC5 > VTH5(MAX),
VCC3 > VTH3(MAX)
RESET Output Voltage High
ISOURCE = 500µA
MIN
TYP
MAX
UNITS
0.8VCC
VOH
V
MAX6351/MAX6353/
MAX6354/MAX6356/
MAX6357/MAX6359/
MAX6360
ISOURCE = 800µA
(L_, M_ versions only),
VCC5 > VTH5(MAX),
VCC3 > VTH3(MAX)
VCC - 1.5
WATCHDOG INPUT (MAX6358/MAX6359/MAX6360)
Watchdog Timeout Period
tWD
WDI Pulse Width (Note 4)
tWDI
WDI Input Threshold (Note 5)
VIL
VIH
First timeout period after reset
25.6
46.4
72.0
After first WDI falling edge
1.6
2.9
4.5
VIL = 0.4V, VIH = 0.8VCC
50
0.7VCC
120
VWDI = VCC
WDI Input Current (Note 6)
ns
0.3VCC
VCC3 = 5V
VWDI = 0
-20
0.8
sec
160
-15
V
µA
MANUAL RESET INPUT
MR Input
VIL
MAX63_ _L_, MAX63_ _M_, VCC5 > VTH5(MAX)
VIH
MAX63_ _L_, MAX63_ _M_, VCC5 > VTH5(MAX)
VIL
MAX63_ _ _Y, VCC5 > VTH5(MAX)
VIH
MAX63_ _ _Y, VCC5 > VTH5(MAX)
MR Pull-Up Resistance
MR Minimum Pulse Width
2.3
0.3VCC
0.7VCC
32
MR Glitch Rejection
MR to Reset Delay
63.5
100
10
tRP
V
tMD
kΩ
µs
100
ns
0.1
µs
ADJUSTABLE RESET COMPARATOR INPUT (MAX6355/MAX6356/MAX6357)
TA = +25°C
1.20
TA = -40°C to +85°C
1.19
RSTIN Input Threshold
VRSTIN
VCC5 > VTH5(MAX),
VCC3 > VTH3(MAX)
RSTIN Input Current
IRSTIN
0 < VRISTIN < VCC5 - 0.3V
RSTIN Hysteresis
1.22
1.24
1.25
-25
25
2.5
V
nA
mV
Note 1: Overtemperature limits are guaranteed by design and not production tested.
Note 2: The reset output is guaranteed to be in the correct state if either VCC3 or VCC5 is within its specified region of operation.
Note 3: The reset output(s) is asserted if either VCC5 or VCC3 drops below its associated trip point.
Note 4: Guaranteed by design. Not production tested.
Note 5: WDI is internally serviced within the watchdog timeout period if WDI is left unconnected.
Note 6: The WDI input current is specified as the average input current when the WDI input is driven high or low.
_______________________________________________________________________________________
3
MAX6351–MAX6360
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(VCC = +5V, TA = +25°C, unless otherwise noted.)
RESET vs. VCC5 (VCC3 = 3V)
4.0
15
5.0
MAX6351/60-02
MAX6351/60-01
4.5
4.0
ICC3 (VCC5 = 5.0V, VCC3 = 3.3V)
5
ICC3 (VCC5 = 3.3V, VCC3 = 2.5V)
3.0
VTH
2.5
2.0
-40
-15
10
35
60
2.5
1.5
1.0
0.5
0.5
0
0
85
MAX6351
MAX6360
2.0
1.0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
TEMPERATURE (°C)
VCC5 (V)
VCC5 (V)
NORMALIZED RESET/WATCHDOG
PERIOD vs. TEMPERATURE
MAXIMUM VCC TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
RESET DELAY vs.
RESET THRESHOLD OVERDRIVE
1.05
1.00
0.95
0.90
250
200
150
100
200
150
100
DELAY FROM FALL OF VCC3
50
50
0.85
MAX6351/60-06
RESET OCCURS ABOVE LINE
RESET DELAY (µs)
1.10
250
MAX6351/60-05
1.15
300
TRANSIENT DURATION (µs)
MAX6351/60-04
1.20
DELAY FROM FALL OF VCC5
0
0
0.80
-60
-40
-20
0
20
40
60
80
0.01
100
0.1
1
RESET THRESHOLD OVERDRIVE, VRST - VCC (V)
TEMPERATURE (°C)
0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
RESET THRESHOLD OVERDRIVE, VRST - VCC (V)
PULL-DOWN CHARACTERISTICS
AND MANUAL RESET DELAY
PULL-UP CHARACTERISTICS
MAX6351/60-07
MAX6351/60-08
5V
5V PUSH-PULL
OUTPUT
5V
MR
0
0
5V
OPEN-DRAIN
OUTPUT
5V
0
OPEN-DRAIN
OUTPUT
0
3V
3V PUSH-PULL
OUTPUT
5V
3V PUSH-PULL
OUTPUT
0
5V PUSH-PULL
OUTPUT
5V
0
0
400ns/div
4
10k
RST
RST3
RST5
3.0
1.5
0
VCC5 OR VCC3
3.5
RESET (V)
ICC5 (VCC5 = 3.3V, VCC3 = 2.5V)
10
VCC
4.5
3.5
RESET (V)
SUPPLY CURRENT (µA)
ICC5 (VCC5 = 5.0V, VCC3 = 3.3V)
RESET vs. VCC5 (VCC3 = GND)
5.0
MAX6351/60-03
SUPPLY CURRENT vs. TEMPERATURE
20
NORMALIZED PERIOD
MAX6351–MAX6360
Dual/Triple-Voltage
µP Supervisory Circuits
40ns/div
_______________________________________________________________________________________
Dual/Triple-Voltage
µP Supervisory Circuits
PIN
MAX6352
MAX6353
MAX6354
MAX6355
MAX6356
MAX6357
MAX6358
MAX6359
MAX6360
NAME
MAX6351
1
—
—
—
RST5
Active-Low, 5V CMOS Reset Output
FUNCTION
—
1
1
1
RST
Active-Low Reset Output. Open-drain for the
MAX6352/MAX6355/MAX6358, 5V push-pull for the
MAX6353/MAX6356/MAX6359, and 3V push-pull for
the MAX6354/MAX6357/MAX6360.
2
2
2
2
GND
Ground
3
3
3
3
MR
Manual-Reset Input. Pull low to force a reset. RST,
RST5, and RST3 remain active as long as MR is low
and for the timeout period after MR goes high.
Leave unconnected or connect to VCC5 if unused.
V MR must be below VCC5.
4
4
4
4
VCC3
+3.3V/+3.0V Supply Input. Powers the device when
it is above VCC5 and monitors its own voltage.
5
—
—
—
RST3
Active-Low, 3V CMOS Reset Output
RSTIN
Undervoltage Reset Comparator Input. Asserts
reset when the monitored voltage falls below 1.23V.
Set the reset threshold with an external resistordivider. Connect to VCC5 if unused. VRSTIN must be
below VCC5.
—
—
5
—
—
—
—
5
WDI
Watchdog Input. If WDI remains either high or low
longer than the timeout period, then reset is triggered. The timer clears when reset is asserted or
whenever WDI sees a rising or falling edge. Leave
floating to disable it if unused.
6
5
6
6
VCC5
+5V Supply Input. Powers the device when it is
above VCC3 and monitors its own voltage.
_______________________________________________________________________________________
5
MAX6351–MAX6360
Pin Description
MAX6351–MAX6360
Dual/Triple-Voltage
µP Supervisory Circuits
Detailed Description
Supply Voltages
The MAX6351–MAX6360 microprocessor (µP) supervisory circuits maintain system integrity by alerting the µP to
fault conditions. These ICs monitor multiple-supply systems and derive their internal power from the highest voltage source present at VCC5 and VCC3. In addition, the
output reset state is guaranteed to remain viable while
either VCC5 or VCC3 is above +1V.
MR
GLITCH
FILTER
VTH5
RST (1)
4 VCC3
RESET
GENERATOR
VTH3
Reset Outputs
The MAX6351 provides a 5V active-low reset and a 3V
active-low reset. The MAX6353/MAX6356/MAX6359 provide a 5V active-low push-pull reset and the MAX6354/
MAX6357/MAX6360 provide a 3V active-low push-pull
reset. The MAX6353/MAX6355/MAX6358 provide an
active-low open-drain reset. The higher input voltages of
VCC5 and VCC3 maintain the sinking capability of the
low reset-output state. The reset outputs are maintained
as long as either supply is above +1V.
3
(5) 6 VCC5
Threshold Levels
All the possible input voltage threshold level combinations are indicated by a two-letter code in Voltage
Threshold Levels. The two standard combinations are
LS and SY. LS parts monitor one +5V ±5% supply and
one +3.3V ±10% supply. SY parts monitor one +3.3V
±10% supply and one +2.5V ±10% supply. The other
combinations also monitor +5V ±10% supplies, +3.3V
±5% supplies, and +3V ±5% supplies.
Negative-Going VCC Transients
The MAX6351–MAX6360 are designed to ignore short
negative-going VCC5 and VCC3 transients. See Typical
Operating Characteristics for a glitch immunity graph.
RST3 (5)
RST5 (1)
Third Input Voltage
(MAX6355/MAX6356/MAX6357)
The MAX6355/MAX6356/MAX6357 provide an additional input to monitor a third voltage. The threshold voltage
at RSTIN is typically 1.22V. To monitor a voltage higher
than 1.22V, connect a resistor-divider to the circuit as
shown in Figure 2. The threshold at V3 is:
(5) (RSTIN)
 R1 + R2 
V3TH = 1.22 


R2 
Note that RSTIN is powered by VCC5, and its voltage
must therefore remain lower than VCC5.
1.22V
(5) (WDI)
WATCHDOG
TIMER
V3
R1
MAX6355
MAX6356
MAX6357
RSTIN
2
GND
MAX6351–MAX6360
NOTE: PIN 1 IS RST5 FOR THE MAX6351 AND RST FOR THE
MAX6352–MAX6360. PIN 5 IS RST3 FOR THE MAX6351, RSTIN
FOR THE MAX6355/56/57, WDI FOR THE MAX6358/59/60,
AND VCC FOR THE MAX6352/53/54.
Figure 1. Functional Diagram
6
R2
VCC5 ≥ VRSTIN
Figure 2. Monitoring a Third Voltage
_______________________________________________________________________________________
Dual/Triple-Voltage
µP Supervisory Circuits
Interfacing to µPs with
Bidirectional Reset Pins
The MAX6358/MAX6359/MAX6360 include a WDI to
provide a reset if the µP goes into an infinite loop. After
a reset, the start-up timeout period and the initial timeout period is nominally 46.4sec to allow the µP time to
initialize. After the first transition on the WDI and after
any toggle of the watchdog thereafter, the timeout period is nominally 2.9sec.
Microprocessors with bidirectional reset pins will contend with the push-pull outputs of these devices. To
prevent this, connect a 4.7kΩ resistor between RESET
and the µP’s reset I/O port, as shown in Figure 5. Buffer
RESET as shown in the figure if this reset is used by
other components in the system.
Applications Information
Ensuring a Valid RESET Output
Down to VCC = 0
VCC5
In some systems, it is necessary to ensure a valid reset
even if VCC falls to 0. In these applications, use the circuit shown in Figure 3. Note that this configuration does
not work for the open-drain outputs of the MAX6352/
MAX6355/MAX6358.
RSTIN
Monitoring a Negative Voltage
To monitor a negative supply rail using RSTIN or the
MAX6355/MAX6356/MAX6357, use the circuit shown in
Figure 4. In this configuration, a reset is issued when
the negative supply falls below VINTH.
MAX6355
MAX6356
MAX6357
R1
R2
VIN
VINTH = 1.22 VCC5 ≥ -
R2
(V 5 - 1.22)
R1 CC
VINR1
R2
VCC5 ≥ VRSTIN
Figure 4. Monitoring a Negative Voltage
BUFFERED RESET TO OTHER SYSTEM COMPONENTS
+3.3V/+3V +5V
VCC3 VCC5
RST
VCC5
RST3
RST5
VCC3
VCC5
100k
VCC3
RST
RST3
RST5
MAX6351–MAX6360
MAX6351–MAX6360
GND
Figure 3. Ensuring a Valid Reset Low to VCC5 and VCC3 = 0
µP
4.7k
RESET
GND
GND
Figure 5. Interfacing to µPs with Bidirectional Reset I/O
Chip Information
TRANSISTOR COUNT: 855
_______________________________________________________________________________________
7
MAX6351–MAX6360
Watchdog Input
(MAX6358/MAX6359/MAX6360)
MAX6351–MAX6360
Dual/Triple-Voltage
µP Supervisory Circuits
Pin Configurations
TOP VIEW
RST5 1
GND 2
MAX6351
MR 3
6
VCC5
RST* 1
5
RST3
GND 2
4
VCC3
MR 3
5
MAX6352
MAX6353
MAX6354
SOT23-6
RST* 1
GND 2
MAX6355
MAX6356
MAX6357
MR 3
VCC5
*MAX6352: OPEN-DRAIN OUTPUT
*MAX6353: 5V PUSH-PULL OUTPUT
*MAX6354: 3V PUSH-PULL OUTPUT
4
VCC3
6
VCC5
5
WDI
4
VCC3
SOT23-5
6
VCC5
5
RSTIN
4
VCC3
RST* 1
*MAX6355: OPEN-DRAIN OUTPUT
*MAX6356: 5V PUSH-PULL OUTPUT
*MAX6357: 3V PUSH-PULL OUTPUT
MAX6358
MAX6359
MAX6360
GND 2
MR 3
SOT23-6
*MAX6358: OPEN-DRAIN OUTPUT
*MAX6359: 5V PUSH-PULL OUTPUT
*MAX6360: 3V PUSH-PULL OUTPUT
SOT23-6
Selector Guide
PART
PIN
COUNT
NUMBER OF
SUPPLIES
MONITORED
5V RESET
3V RESET
OPEN-DRAIN
RESET
WATCHDOG
TIMER
MANUAL
RESET
MAX6351
6
2
✔
✔
—
✔
MAX6352
5
2
—
—
✔
MAX6353
5
2
—
✔
—
✔
—
—
✔
MAX6354
5
2
—
—
✔
MAX6355
6
3
—
✔
MAX6356
6
3
—
✔
—
✔
—
—
✔
MAX6357
6
3
—
6
2
—
✔
MAX6359
6
2
—
✔
—
✔
✔
MAX6358
—
✔
✔
MAX6360
6
2
—
—
✔
✔
—
✔
—
—
✔
—
—
✔
✔
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.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1999 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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