MAX6446UK46L+T [MAXIM]
Power Supply Support Circuit, Fixed, 1 Channel, +4.63VV, BICMOS, PDSO5, LEAD FREE, MO-178AA, SOT-23, 5 PIN;
| 型号： | MAX6446UK46L+T |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Power Supply Support Circuit, Fixed, 1 Channel, +4.63VV, BICMOS, PDSO5, LEAD FREE, MO-178AA, SOT-23, 5 PIN 信息通信管理 光电二极管 |
| 文件： | 总13页 (文件大小：1216K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
General Description
Features
● Single or Dual-Supply Voltage Monitors
The MAX6443–MAX6452 low-current microprocessor
reset circuits feature single or dual manual reset inputs
with an extended setup period. Because of the extended
setup period, short switch closures (nuisance resets) are
ignored.
● Precision Factory-Set Reset Thresholds from
1.6V to 4.6V
● Adjustable Threshold to Monitor Voltages Down to
0.63V (MAX6449–MAX6452)
● Single or Dual Manual Reset Inputs with Extended
Setup Period
● Optional Short Setup Time Manual Reset Input
(MAX6447/MAX6448 and MAX6451/MAX6452)
● Immune to Short Voltage Transients
● Low 6µA Supply Current
On all devices, the reset output asserts when any of
the monitored supply voltages drops below its specified
threshold. The reset output remains asserted for the reset
timeout period (210ms typ) after all monitored supplies
exceed their reset thresholds. The reset output is one-
shot pulse asserted for the reset timeout period (140ms
min) when selected manual reset input(s) are held low for
an extended setup timeout period. These devices ignore
manual reset transitions of less than the extended setup
timeout period.
● Guaranteed Valid Reset Down to V
= 1.0V
CC
● Active-Low RESET (Push-Pull or Open-Drain)
Outputs
● 140ms (min) Reset Timeout Period
● Small SOT143 and SOT23 Packages
The MAX6443–MAX6448 are single fixed-voltage µP
supervisors. The MAX6443/MAX6444 have a single
extended manual reset input. The MAX6445/MAX6446
have two extended manual reset inputs. The MAX6447/
MAX6448 have one extended and one immediate manual
reset input.
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
4 SOT143
MAX6443US_ _ _+T
-40°C to +85°C
MAX6444US_ _ _+T
-40°C to +85°C
4 SOT143
4 SOT143
MAX6444US_ _ _/V+T* -40°C to +85°C
The MAX6449–MAX6452 have one fixed-threshold µP
supervisor and one adjustable-threshold µP supervisor.
The MAX6449/MAX6450 have two delayed manual reset
inputs. The MAX6451/MAX6452 have one delayed and
one immediate manual reset input.
Note: The first “_ _” is a placeholder for the threshold voltage level
of the devices. A desired threshold level is set by the two-number
suffix found in Table 1. The third “_” is a placeholder for the manual
reset setup period of the devices. A desired setup period is set by
the letter suffix found in Table 2. All devices are available in tape-
and-reel only. There is a 2500-piece minimum order increment for
standard versions (Table 2). Sample stock is typically held on stan-
dard versions only. Nonstandard versions require a minimum order
increment of 10,000 pieces. Contact factory for availability.
Most devices are available in lead(Pb)-free packaging only. See
Ordering Information for devices available in both leaded and
lead(Pb)-free packaging.
The MAX6443–MAX6452 have an active-low RESET with
push-pull or open-drain output logic options. These devic-
es, offered in small SOT packages, are fully guaranteed
over the extended temperature range (-40°C to +85°C).
Applications
● Set-Top Boxes
● Consumer Electronics
● DVD Players
/V denotes an automotive qualified part.
*Future product—contact factory for availability.
+Denotes Lead(Pb)-free packages and - denotes leaded packages.
For top mark information, please go to https://www.maximinte-
grated.com/en/design/packaging/topmark/.
● Cable/DSL Modems
● MP3 Players
Pin Configurations
● Industrial Equipment
● Automotive
● Medical Devices
TOP VIEW
1
4
3
GND
V
CC
MAX6443
MAX6444
Ordering Information continued at end of data sheet.
2
MR1
RESET
SOT143
Pin Configurations continued at end of data sheet.
19-2656; Rev 5; 12/15
MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Absolute Maximum Ratings
(All voltages referenced to GND.)
Operating Temperature Range........................... -40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range............................ -65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow)
V
........................................................................-0.3V to +6V
CC
Open-Drain RESET ................................................-0.3V to +6V
Push-Pull RESET .................................... -0.3V to (V
+ 0.3V)
CC
MR1, MR2, MR2, RSTIN ........................................-0.3V to +6V
Input Current, All Pins ......................................................±20mA
Lead(Pb)-free...............................................................+260°C
Containing lead............................................................+240°C
Continuous Power Dissipation (T = +70°C)
A
4-Pin SOT143 (derate 4.0mW/°C above +70°C) ........320mW
5-Pin SOT23 (derate 7.1mW/°C above +70°C) ..........571mW
6-Pin SOT23 (derate 8.7mW/°C above +70°C) ..........696mW
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
(V
= 1.0V to 5.5V, T = -40°C to +85°C, unless otherwise specified. Typical values are at T = +25°C.) (Note 1)
CC
A
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
5.5
UNITS
Operating Voltage Range
V
1.0
V
CC
V
V
= 5.5V, no load
7
20
CC
V
Supply Current
I
µA
CC
CC
= 3.6V, no load
6
16
CC
46
44
31
29
26
23
22
17
16
4.50
4.25
3.00
2.85
2.55
2.25
2.12
1.62
1.52
4.63
4.38
3.08
2.93
2.63
2.32
2.19
1.67
1.58
60
4.75
4.50
3.15
3.00
2.70
2.38
2.25
1.71
1.62
V
Reset Threshold
V
V
CC
TH
Reset Threshold Tempco
Reset Threshold Hysteresis
ppm/°C
mV
2 × V
TH
T
T
= 0°C to +85°C
0.615
0.630
0.645
0.650
A
RSTIN Threshold
V
MAX6449–MAX6452
V
TH-RSTIN
= -40°C to +85°C 0.610
A
RSTIN Threshold Hysteresis
RSTIN Input Current
V
MAX6449–MAX6452
MAX6449–MAX6452
2.5
mV
nA
HYST
I
-25
+25
280
RSTIN
MAX6449–MAX6452, V
1mV/µs
falling at
RSTIN
RSTIN to Reset Output Delay
Reset Timeout Period
15
µs
t
t
140
210
20
ms
µs
RP
V
to RESET Output Delay
V
K
L
falling at 1mV/µs
CC
RD
CC
6.72
4.48
2.24
1.12
10.08
6.72
3.36
1.68
13.44
8.96
4.48
2.24
Manual Reset Minimum Setup
Period Pulse Width
t
s
MR
S
T
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Electrical Characteristics (continued)
(V
= 1.0V to 5.5V, T = -40°C to +85°C, unless otherwise specified. Typical values are at T = +25°C.) (Note 1)
CC
A
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MR2 Minimum Setup Period
Pulse Width
MAX6447/MAX6448/MAX6451/MAX6452
1
µs
MR2 Glitch Rejection
MAX6447/MAX6448/MAX6451/MAX6452
MAX6447/MAX6448/MAX6451/MAX6452
100
200
210
50
ns
ns
MR2 to RESET Delay
Manual Reset Timeout Period
t
140
25
280
75
ms
kW
kW
MRP
MR1 to V
MR2 to V
Pullup Impedance
Pullup Impedance
CC
MAX6445/MAX6446/MAX6449/MAX6450
25
50
75
CC
V
≥ 1.00V, I
= 50µA, RESET
= 100µA, RESET
= 1.2mA, RESET
= 3.2mA, RESET
= 200µA, RESET
CC
SINK
SINK
SINK
SINK
0.3
0.3
0.3
0.4
asserted
V
≥ 1.20V, I
CC
asserted
RESET Output Low
V
V
OL
(Open Drain or Push-Pull)
V
≥ 2.55V, I
CC
asserted
V
≥ 4.25V, I
CC
asserted
V
≥ 1.80V, I
CC
SOURCE
SOURCE
SOURCE
0.8 × V
0.8 × V
0.8 × V
CC
CC
CC
deasserted
RESET Output High
V
≥ 3.15V, I
= 500µA, RESET
= 800µA, RESET
CC
V
I
V
OH
(Push-Pull)
deasserted
V
≥ 4.75V, I
CC
deasserted
RESET Open-Drain Leakage
RESET deasserted
1
µA
V
LKG
Current
MR1, MR2, MR2
V
0.3 × V
CC
IL
Input Low Voltage
MR1, MR2, MR2
V
0.7 × V
V
IH
CC
Input High Voltage
Note 1: Devices production tested at T = +25°C. Overtemperature limits are guaranteed by design.
A
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Typical Operating Characteristics
(V
= 3.3V, T = +25°C, unless otherwise noted.)
A
CC
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
NORMALIZED RESET TIMEOUT PERIOD
vs. TEMPERATURE
MAXIMUM TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
1.05
250
200
150
100
50
9
8
7
6
5
4
3
2
1
0
T
= +85°C
1.04
1.03
1.02
1.01
1.00
0.99
0.98
0.97
0.96
0.95
A
T
= +25°C
A
RESET OCCURS
ABOVE THE CURVE
T
= -40°C
A
V
TH
= 4.4V
800
0
-40
-15
10
35
60
85
0
200
400
600
1000
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
RESET THRESHOLD OVERDRIVE (mV)
N
ORMALIZED V RESET THRESHOLD
V
CC
TO RESET DELAY
RSTIN TO RESET DELAY
CC
vs. TEMPERATURE
vs. TEMPERATURE
vs. TEMPERATURE (RSTIN FALLING)
1.03
1.02
1.01
1.00
0.99
0.98
0.97
24.0
23.6
23.2
22.8
22.4
22.0
21.6
21.2
20.8
20.4
20.0
24.0
23.6
23.2
22.8
22.4
22.0
21.6
21.2
20.8
20.4
20.0
V
= FALLING AT 1mV/µs
RSTIN FALLING AT 1mV/µs
CC
-40
-15
10
35
60
85
-40
-15
10
35
60
85
-40
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
MANUAL RESET TO RESET DELAY
(MAX6445L/MAX6446L/MAX6449L/MAX6450L)
V
CC
TO RESET DELAY
MAX6443/52 toc08
MAX6443/52 toc07
V
= 5V
CC
MR1
(5V/div)
V
CC
= 4.5V
V
TH
= 4.392V
V
(100mV/div)
CC
V
CC
= 4.3V
MR2
(5V/div)
RESET
(5V/div)
RESET
(2V/div)
TIME (1s/div)
TIME (100µs/div)
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Pin Description
PIN
NAME
FUNCTION
MAX6443 MAX6445 MAX6447 MAX6449 MAX6451
MAX6444 MAX6446 MAX6448 MAX6450 MAX6452
1
2
2
2
2
GND
Ground
Active-Low Push-Pull or Open-Drain Output. RESET
changes from high to low when V or RSTIN drops below
CC
its selected reset threshold and remains low for the 210ms
reset timeout period after all monitored power-supply inputs
RESET exceed their selected reset thresholds. RESET is one-shot
pulsed low for the reset timeout period (140ms min) after
selected manual reset inputs are asserted longer than the
specified setup period. For the open-drain output, use a
2
1
1
1
1
minimum 20kW pullup resistor to V
.
CC
Manual Reset Input, Active Low. Internal 50kW pullup to
Pull MR1 low for the typical input pulse width (t )
MR
3
—
3
—
3
V
CC.
to one-shot pulse RESET for the reset timeout period.
MR1
Manual Reset Input, Active Low. Pull both MR1 and
—
4
3
4
—
4
3
4
—
4
MR2 low for the typical input pulse width (t ) to one-
MR
shot pulse RESET for the reset timeout period.
V
Voltage Input. Power supply and input for the
CC
V
CC
primary microprocessor voltage reset monitor.
Manual Reset Input, Active Low. Internal 50kW pullup to
V
. Pull both MR1 and MR2 low for the typical input
CC
—
—
—
5
—
5
6
—
5
—
6
MR2
MR2
pulse width (t
) to one-shot pulse RESET for the reset
MR
timeout period.
Manual Reset Input. Pull the MR2 high to immediately
one-shot pulse RESET for the reset timeout period.
—
—
Reset Input. High-impedance input to the adjustable
reset comparator. Connect RSTIN to the center point
of an external resistor-divider to set the threshold of the
externally monitored voltage.
—
5
RSTIN
threshold voltages. Once V
and V
exceed their
RSTIN
CC
Detailed Description
respective reset threshold voltages, RESET remains low
for the reset timeout period and then goes high. RESET
is one-shot pulsed whenever selected manual reset
inputs are asserted. RESET stays asserted for the nor-
mal reset timeout period (140ms min).
Reset Output
The reset output is typically connected to the reset
input of a microprocessor (µP). A µP’s reset input starts
or restarts the µP in a known state. The MAX6443–
MAX6452 µP supervisory circuits provide the reset
logic to prevent code-execution errors during power-
up, power-down and brownout conditions (see the
Typical Operating Circuit).
RESET is guaranteed to be in the proper output logic
state for V
inputs ≥ 1V. For applications requiring valid
CC
reset logic when V
is less than 1V, see the Ensuring a
CC
Valid RESET Output Down to V
= 0V section.
CC
RESET changes from high to low whenever the moni-
tored voltages (RSTIN or V ) drop below the reset
CC
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Manual Reset Input Options
RESET TIMEOUT PERIOD
210ms
Unlike typical manual reset functions associated with
supervisors, each device in the MAX6443–MAX6452 fam-
ily includes at least one manual reset input, which must be
MR1 SETUP PERIOD
t
MR
held logic-low for an extended setup period (t ) before
MR1
MR
the RESET output asserts. When valid manual reset input
conditions/setup periods are met, the RESET output is
one-shot pulse asserted low for a fixed reset timeout peri-
od (140ms min). Existing front-panel pushbutton switches
(i.e., power on/off, channel up/down, or mode select) can
be used to drive the manual reset inputs. The extended
manual reset setup period prevents nuisance system
resets during normal front-panel usage or resulting from
inadvertent short-term pushbutton closure.
RESET
Figure 1. MAX6443/MAX6444 Manual Reset Timing Diagram
210ms
MR1
The MAX6443/MAX6444, MAX6447/MAX6448, and
MAX6451/MAX6452 include a single manual reset
input with extended setup period (MR1). The MAX6445/
MAX6446 and MAX6449/MAX6450 include two manual
reset inputs (MR1 and MR2) with extended setup peri-
ods. For dual MR1, MR2 devices, both inputs must be
held low simultaneously for the extended setup period
t
MR
MR2
RESET
(t ) before the reset output is pulse asserted. The
MR
Figure 2. MAX6445/MAX6446/MAX6449/MAX6450 Manual
Reset Timing Diagram
dual extended setup provides greater protection from
nuisance resets. (For example, the user or service
technician is informed to simultaneously push both the
on/off button and the channel-select button for 6.72s
(L suffix) to reset the system.)
there are no false RESET assertions when MR2 is driven
from high to low (Figure 4). The MR2 input can be used
for system test purposes or smart-card-detect applica-
tions (see the Applications Information section).
The MAX6443/MAX6452 RESET output is pulse asserted
once for the reset timeout period after each valid manual
reset input condition. At least one manual reset input
must be released (go high) and then be driven low for
the extended setup period before RESET asserts again.
Internal timing circuitry debounces low-to-high manual
reset logic transitions, so no external circuitry is required.
Figure 1 illustrates the single manual reset function of
the MAX6443/MAX6444 single-voltage monitors, and
Figure 2 represents the dual manual reset function of the
MAX6445/MAX6446 and MAX6449/MAX6450.
Adjustable Input Voltage (RSTIN)
The MAX6449–MAX6452 monitor the voltage on RSTIN
using an adjustable reset threshold set with an external
resistor voltage-divider (Figure 5). Use the following
formula to calculate the externally monitored voltage
(V
):
MON-TH
V
= V
× (R1 + R2)/R2
MON-TH
TH-RSTIN
where V
is the desired reset threshold voltage and
MON-TH
V
is the reset input threshold (0.63V). Resistors
TH-RSTIN
R1 and R2 can have very high values to minimize current
consumption because of low leakage currents. Set R2 to
some conveniently high value (250kW, for example), and
calculate R1 based on the desired reset threshold volt-
age, using the following formula:
The MAX6447/MAX6448 and MAX6451/MAX6452
include both an extended setup period and immediate
setup period manual reset inputs. A low-to-high MR2
rising edge transition immediately pulse asserts the
RESET output for the reset timeout period (140ms min).
If the MAX6447/MAX6448 and MAX6451/MAX6452
MR2 input senses another rising edge before the end
of the 140ms timeout period (Figure 3), the internal
timer clears and begins counting again. If no rising
edges are detected within the 210ms timeout period,
RESET deasserts. The high-to-low transition on MR2
input is internally debounced for 210ms to ensure that
R1 = R2 × (V
/V
- 1) W
MON-TH TH-RSTIN
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
t < 210ms
COUNTER RESET
210ms
DEBOUNCING PERIOD
POSITIVE EDGE
t = 210ms
210ms
TIMEOUT PERIOD
MR2
MR2
NO RESET
OUTPUT
RESET
ASSERTED
RESET
Figure 3. MAX6447/MAX6448/MAX6451/MAX6452 MR2
Assertion DebouncingTiming Diagram
Figure 4. MAX6447/MAX6448/MAX6451/MAX6452 MR2
Deassertion Debouncing Timing Diagram
+3.3V
V
V
CC
MON_TH
MAX6449
MAX6451
R1
R2
V
CC
V
RESET
RESET
CC
RSTIN
GND
V
CC
MAX6443L
µP
LED
RESET
GND
MR1
NMI
V
= 0.63 x (R1 + R2) / R2
MON_TH
PUSHBUTTON SWITCH:
CLOSE FOR < 4.48s
Figure 5. Calculating the Monitored Threshold Voltages
FOR SYSTEM INTERRUPT;
CLOSE FOR > 6.72s FOR
SYSTEM RESET
Applications Information
Interrupt Before Reset
Figure 6. Interrupt Before Reset Application Circuit
To minimize data loss and speed system recovery,
many applications interrupt the processor or reset only
portions of the system before a processor hard reset is
asserted. The extended setup time of the MAX6443–
MAX6452 manual reset inputs allows the same push-
button (connected to both the processor interrupt and
the extended MR1 input, as shown in Figure 6) to
control both the interrupt and hard reset functions. If the
closed long enough for a hard reset (the same LED might
be used as the front-panel power-on display).
Smart Card Insertion/Removal
The MAX6447/MAX6448/MAX6451/MAX6452 dual man-
ual resets are useful in applications in which both an
extended and immediate setup periods are needed.
Figure 7 illustrates the insertion and removal of a smart
card. MR1 monitors a front-panel pushbutton. When
pushbutton is closed for less than t , the processor
MR
is only interrupted. If the system still does not respond
properly, the pushbutton (or two buttons for the dual
manual reset) can be closed for the full extended setup
period to hard reset the processor. If desired, connect
an LED to the RESET output to blink off (or on) for the
reset timeout period to signify when the pushbutton is
closed for t , RESET one-shot pulses low for 140ms
MR
min. Because MR1 is internally pulled to V
through a
CC
50kW resistor, the front-panel switch can be connected
to a microprocessor for general-purpose I/O control.
MR2 monitors a switch to detect when a smart card is
inserted. When the switch is closed high (card inserted),
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
+3.3V
+1.5V
3.3V
5V
CORE SUPPLY I/O SUPPLY
V
RESET
RESET
V
CC
CC
MAX6451
MAX6444
MAX6446
MAX6448
MAX6450
MAX6452
µP
100kΩ
µP
DIGITAL INPUT
RSTIN
MR1
MR2
RESET
RESET
GND
N
SMART CARD DETECT:
IMMEDIATE ONE-SHOT
WHEN MANUAL
GND
RESET CLOSES
FRONT-PANEL SWITCH
STANDARD µP INPUT
AND t MANUAL
MR
RESET DELAY
Figure 8. Interfacing to Other Voltage Levels
Figure 7. MAX6451/MAX6452 Application Circuit
RESET one-shot pulses low for 140ms. MR2 is internally
debounced for 210ms to prevent false resets when the
smart card is removed.
Ensuring a Valid RESET Down to
= 0V (Push-Pull RESET)
V
CC
When V
falls below 1V, RESET current-sinking capabil-
CC
ities decline drastically. The high-impedance CMOS-logic
inputs connected to RESET can drift to undetermined
voltages. This presents no problems in most applications,
because most µPs and other circuitry do not operate with
Interfacing to Other Voltages
for Logic Compatibility
The open-drain RESET output can be used to interface
to a µP with other logic levels. As shown in Figure 8, the
open-drain output can be connected to voltages from 0
to 6V.
V
below 1V.
CC
In applications in which RESET must be valid down to 0V,
add a pulldown resistor between RESET and GND for the
push-pull outputs. The resistor sinks any stray leakage
currents, holding RESET low (Figure 9). The value of the
pulldown resistor is not critical; 100kW is large enough
not to load RESET and small enough to pull RESET to
ground. The external pulldown cannot be used with the
open-drain reset outputs.
Generally, the pullup resistor connected to the RESET
connects to the supply voltage that is being monitored
at the IC’s V
pin. However, some systems may use
CC
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 supervisor’s V
decreases toward 1V, so does the IC’s ability to sink
current at RESET. RESET is pulled high as V decays
CC
Transient Immunity
CC
toward 0. The voltage where this occurs depends on
the pullup resistor value and the voltage to which it is
connected.
In addition to issuing a reset to the µP during pow-
er-up, power-down, and brownout conditions, these
supervisors are relatively immune to short-duration fall-
ing transients (glitches). The graph Maximum Transient
Duration vs. Reset Threshold Overdrive in the Typical
Operating Characteristics section shows this relationship.
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
The area below the curves of the graph is the region in
which these devices typically do not generate a reset
pulse. This graph was generated using a falling pulse
V
CC
applied to V , starting above the actual reset threshold
(V ) and ending below it by the magnitude indicated
TH
(reset threshold overdrive). As the magnitude of the tran-
MAX6443
CC
V
CC
MAX6445
MAX6447
MAX6449
MAX6451
sient increases (V
goes further below the reset thresh-
CC
old), the maximum allowable pulse width decreases.
Typically, a V transient that goes 100mV below the
reset threshold and lasts 20µs or less does not cause a
reset pulse to be asserted.
RESET
CC
100kΩ
GND
Figure 9. Ensuring RESET Valid to V
= 0V
CC
Table 1. Reset Voltage Threshold
VCC NOMINAL
PART NO. SUFFIX
( _ _ )
VOLTAGE
THRESHOLD (V)
46
44
31
29
26
23
22
17
16
4.625
4.375
3.075
2.925
2.625
2.313
2.188
1.665
1.575
Table 2. Manual Reset Setup Period (t
)
MR
PART NO. SUFFIX
( _ )
MANUAL RESET SETUP
PERIOD (s)
10.08
6.72
K
L
S
T
3.36
1.68
Maxim Integrated
│ 9
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Pin Configurations (continued)
TOP VIEW
RESET
GND
1
2
3
5
4
MR2
RESET
GND
1
2
3
5
4
MR2
MAX6445
MAX6446
MAX6447
MAX6448
MR1
V
CC
MR1
V
CC
SOT23-5
SOT23-5
RESET
GND
1
2
3
6
5
4
MR2
RESET
GND
1
2
3
6
5
4
MR2
MAX6451
MAX6452
MAX6449
MAX6450
RSTIN
RSTIN
MR1
V
MR1
V
CC
CC
SOT23-6
SOT23-6
Ordering Information (continued)
Typical Operating Circuit
PART
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
5 SOT23
5 SOT23
5 SOT23
5 SOT23
6 SOT23
6 SOT23
6 SOT23
6 SOT23
+3.3V
MAX6445UK_ _ _+T
MAX6446UK_ _ _+T
MAX6447UK_ _ _+T
MAX6448UK_ _ _+T
MAX6449UT_ _ _+T
MAX6450UT_ _ _+T
MAX6451UT_ _ _+T
MAX6452UT_ _ _+T
V
CC
V
CC
MAX6444
µP
MR1
RESET
RESET
GND
GND
RESET TIMEOUT PERIOD
210ms
Note: The first “_ _” is a placeholder for the threshold voltage level
of the devices. A desired threshold level is set by the two-number
suffix found in Table 1. The third “_” is a placeholder for the manual
reset setup period of the devices. A desired setup period is set by
the letter suffix found in Table 2. All devices are available in tape-
and-reel only. There is a 2500-piece minimum order increment for
standard versions (Table 2). Sample stock is typically held on standard
versions only. Nonstandard versions require a minimum order increment
of 10,000 pieces. Contact factory for availability.
MR1 SETUP PERIOD
t
MR
MR1
RESET
Most devices are available in lead(Pb)-free packaging only. See
Ordering Information for devices available in both leaded and
lead(Pb)-free packaging.
/V denotes an automotive qualified part.
*Future product—contact factory for availability.
+Denotes Lead(Pb)-free packages and - denotes leaded packages.
For top mark information, please go to https://www.maximinte-
grated.com/en/design/packaging/topmark/.
Maxim Integrated
│ 10
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Selector Guide
MR1 EXT.
MR2
(NO SETUP)
MR2 EXT.
PART
RSTIN PUSH-PULL RESET OPEN-DRAIN RESET
SETUP
SETUP
MAX6443
MAX6444
MAX6445
MAX6446
MAX6447
MAX6448
MAX6449
MAX6450
MAX6451
MAX6452
—
—
—
—
✔
✔
—
—
✔
✔
—
—
✔
✔
—
—
✔
✔
—
—
—
—
—
—
—
—
✔
✔
✔
✔
—
✔
—
✔
—
✔
—
✔
—
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
—
✔
—
✔
—
✔
—
✔
—
Functional Diagram
V
CC
MAX6443–
MAX6452
RESET
TIMEOUT PERIOD
(210ms typ)
RESET
RSTIN
MAX6449–
MAX6452
MAX6447
MAX6448
MAX6451
MAX6452
V
MR2 ONE-SHOT
DEBOUNCE
CIRCUIT
MANUAL RESET
SETUP PERIOD
CC
MR2
0.63V
t
MR
1.23V
V
CC
V
CC
GND
MR1
MR2
MAX6445
MAX6446
MAX6449
MAX6450
Maxim Integrated
│ 11
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Chip Information
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.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.
PACKAGE
TYPE
PACKAGE OUTLINE
LAND
PATTERN NO.
CODE
NO.
4 SOT143
5 SOT23
6 SOT23
U4+1
21-0052
21-0057
21-0058
90-0183
90-0174
90-0175
U5+1, U5-1
U6+1
Maxim Integrated
│ 12
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MAX6443–MAX6452
µP Reset Circuits with Long Manual Reset
Setup Period
Revision History
REVISION REVISION
PAGES
DESCRIPTION
CHANGED
NUMBER
DATE
0
10/02
Initial release
—
Revised the General Description, Features, Applications, Ordering Information,
Absolute Maximum Ratings, Electrical Characteristics, Typical Operating
Characteristics, Pin Description, the Manual Reset Input Options, Interrupt Before
Reset, and Smart Card Insertion/Removal sections, Functional Diagram, Typical
Operating Circuit, Selector Guide, Figures 1, 6, and 7, as well as Tables 2 and 3 to
add extended setup timeout specifications
3
6/10
1, 2, 4, 5–12
4
5
3/14
Added the automotive MAX6444US_ _ _/V+T to the Ordering Information table
1
Added lead-free package part numbers, removed top mark table and added
reference to top mark information on website
12/15
1, 10, 12
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
©
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
2015 Maxim Integrated Products, Inc.
│ 13
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