MAX7387CMAC [MAXIM]
Power Supply Management Circuit, Fixed, 1 Channel, BICMOS, PDSO10, 3 X 3 MM, MO-187CBA, MICRO, SOP-10;![MAX7387CMAC](http://pdffile.icpdf.com/pdf2/p00288/img/icpdf/MAX7388ANVB_1746950_icpdf.jpg)
型号: | MAX7387CMAC |
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描述: | Power Supply Management Circuit, Fixed, 1 Channel, BICMOS, PDSO10, 3 X 3 MM, MO-187CBA, MICRO, SOP-10 信息通信管理 光电二极管 |
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19-3896; Rev 1; 1/06
System Monitoring Oscillator with
Watchdog and Power Fail
General Description
Features
The MAX7387/MAX7388 replace ceramic resonators,
crystals, and supervisory functions for microcontrollers
in 3.3V and 5V applications.
♦ Robust Microcontroller Clock and Supervisor in a
Single Package
♦ Integrated Reset, Watchdog, and Power-Fail
The MAX7387/MAX7388 provide a clock source together
with integrated reset, watchdog, and power-fail func-
tions. The watchdog timer is pin programmable and
provides watchdog timeout values in the 16ms to
2048ms range. The power-fail output provides early
warning of power failure. The power-fail threshold on the
MAX7388 is internally set. The MAX7387 also provides
a separate watchdog output that is used as a status
indicator or to control safety-critical system elements.
Functions
♦ Pin-Programmable Watchdog Timeout
♦ +2.7V to +5.5V Operation
♦ Factory-Trimmed Oscillator
♦ Reset Valid Down to 1.1V Supply Voltage
♦ ±1ꢀmꢁ Clock-Output Drive Current
♦ ±±4 Total ꢁccuracy ꢂor -±ꢀ0C to +1250C
♦ ±2.754 Total ꢁccuracy ꢂor ꢀ0C to +ꢃ50C
♦ -±ꢀ0C to +1250C Temperature Range
The MAX7387/MAX7388 clock outputs are factory pro-
grammed to a frequency in the 1MHz to 16MHz range.
Four standard frequencies are available. Other frequen-
cies are available upon request. The maximum operating
supply current is 5.5mA (max) with a clock frequency of
12MHz.
♦ ꢃ- and 1ꢀ-Pin µMꢁX Surꢂace-Mount Packages
♦ 5.5mꢁ Operating Current (12MHz)
Unlike typical crystal and ceramic resonator oscillator
circuits, the MAX7387/MAX7388 are resistant to EMI
and vibration, and operate reliably at high tempera-
tures. The high-output drive current and absence of
high-impedance nodes make the oscillator invulnerable
to dirty or humid operating conditions.
♦ 1MHz to 16MHz Factory Preset Frequency
Ordering Information
PꢁRT
TEMP RꢁNGE PIN-PꢁCKꢁGE PKG CODE
MꢁX73ꢃ7srff -40oC to +125oC 10 µMAX
MꢁX73ꢃꢃsrff -40oC to +125oC 8 µMAX
U10-2
U8-1
The MAX7387/MAX7388 are available in 10-pin and 8-pin
µMAX® packages, respectively. The MAX7387/MAX7388
standard operating temperature range is from -40°C to
+125°C.
Note: “s” is a placeholder for the reset output type. Insert the
symbol found in Table 3 in the place of “s.” “r” is a placeholder
for the power-on reset (POR) voltage. Insert the symbol found in
Table 2 in the place of “r.” “ff” is a placeholder for the nominal
output frequency. Insert the symbol found in Table 4 in the
place of “ff.” For example, MAX7387CMTP describes a device
with 4.38V reset level, open-collector RST output, and a clock
output frequency of 8MHz.
Applications
White Goods
Automotive
Handheld Products
Portable Equipment
Appliances and Controls Microcontroller Systems
Typical Application Circuit, Functional Diagram, and Selector
Guide appear at end of data sheet.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Pin Configurations
TOP VIEW
TOP VIEW
PFI
1
2
3
4
5
10 CLOCK
V
1
2
3
4
8
7
6
5
CLOCK
RST/RST
WDI
CC
V
CC
9
8
7
6
RST/RST
WDI
WDS1
WDS2
GND
MAX7387
MAX7388
WDS1
WDS2
GND
PFO
PFO
WDO
µMꢁX
µMꢁX
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
System Monitoring Oscillator with
Watchdog and Power Fail
ꢁBSOLUTE MꢁXIMUM RꢁTINGS
CC
All Other Pins to GND ................................-0.3V to (V
CLOCK, PFO Output Current, RST/RST, WDO................. 50mA
V
to GND...........................................................-0.3V to +6.0V
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
+ 0.3V)
CC
Continuous Power Dissipation (T = +70°C)
A
10-Pin µMAX (derate 5.6mW/°C over +70°C)..............444mW
8-Pin µMAX (derate 4.5mW/°C over +70°C) ................362mW
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.
ELECTRICꢁL CHꢁRꢁCTERISTICS
(Typical Application Circuit, V
= +2.7V to +5.5V, T = -40°C to +125°C, 1MHz to 16MHz output frequency range, typical values at
CC
A
V
= +5.0V, T = +25°C, unless otherwise noted.) (Note 1)
CC
A
PꢁRꢁMETER
SYMBOL
CONDITIONS
MIN
TYP
MꢁX
UNITS
POWER REQUIREMENTS
Operating Supply Voltage
V
2.7
5.5
1.1
V
V
CC
T
T
= 0°C to +85°C
A
Valid RST/RST Supply Voltage
V
CCR
= -40°C to +125°C
1.18
5.5
A
f
f
= 12MHz
= 8MHz
CLOCK
CLOCK
Operating Supply Current
I
mA
CC
4.5
TRI-LEVEL ꢁNꢁLOG INPUTS: WDS1, WDS2
Input-High Voltage Level
V
- 0.55V
V
V
V
CC
Input-Middle Voltage Level
Input-Low Voltage Level
0.9
V
- 1.1V
0.45
CC
LOGIC INPUT: WDI
Input Leakage Current
Logic-Input High Voltage
Logic-Input Low Voltage
I
Input high
0.5
µA
V
LEAK
V
0.7 x V
CC
IH
V
0.3 x V
V
IL
CC
PUSH-PULL LOGIC OUTPUTS: RST/RST
Output High
Output Low
V
I
I
= 1mA
V
- 1.5
V
V
OH
SOURCE
CC
V
= 3mA
SINK
0.05
0.05
0.4
0.4
OL
OPEN-DRꢁIN LOGIC OUTPUTS: RST, PFO, WDO
Output Low
V
I
= 3mA
V
OLO
SINK
OUTPUT: CLOCK
Output High Voltage
Output Low Voltage
V
I
I
= 5mA
V
- 0.3
V
V
OHC
SOURCE
CC
V
= 5mA
SINK
0.3
+2.75
+4
OLC
T
T
= 0°C to +85°C, V
= 5.0V
CC
-2.75
-4
A
A
CLOCK Accuracy
f
%
CLOCK
= -40°C to +125°C, V
= 5.0V
CC
Clock Frequency Temperature
Coefficient
V
= 5.0V (Note 2)
140
400
ppm/°C
CC
Clock Frequency Supply
Voltage Coefficient
T
= +25°C (Note 2)
0.67
50
1
%/V
%
A
CLOCK Duty Cycle
(Note 2)
45
55
2
_______________________________________________________________________________________
System Monitoring Oscillator with
Watchdog and Power Fail
ELECTRICꢁL CHꢁRꢁCTERISTICS (continued)
(Typical Application Circuit, V
= +2.7V to +5.5V, T = -40°C to +125°C, 1MHz to 16MHz output frequency range, typical values at
CC
A
V
= +5.0V, T = +25°C, unless otherwise noted.) (Note 1)
CC
A
PꢁRꢁMETER
SYMBOL
CONDITIONS
MIN
TYP
MꢁX
UNITS
Observation for 20s using a 500MHz
oscilloscope
ps
CLOCK Output Jitter
310
RMS
Output Rise Time
t
C
C
= 10pF, 10% to 90% of full scale (Note 2)
= 10pF, 90% to 10% of full scale (Note 2)
2.5
2.8
7.0
7.5
ns
ns
R
LOAD
LOAD
Output Fall Time
t
F
INTERNꢁL POWER-ON RESET
V
V
TH
+ 1.5%
TH
T
T
= +25°C
A
A
- 1.5%
V
V
V
rising, Table 2
TH+
CC
CC
V
V
TH
+ 2.5%
TH
= -40°C to +125°C
Reset Voltage
V
- 2.5%
0.98 x
V
falling
TH-
V
TH+
Reset Timeout Period
t
Figures 1, 2
86
135
250
µs
RST
WꢁTCHDOG
WDS1 = GND, WDS2 = GND
WDS1 = open, WDS2 = GND
11
22
16
32
22
44
WDS1 = V , WDS2 = GND
CC
44
64
88
WDS1 = GND, WDS2 = open
WDS1 = open, WDS2 = open
88
128
256
512
1024
2048
177
354
708
1416
2832
ms
Watchdog Timeout Period
(Figure 2)
t
177
354
708
1416
WDG
WDS1 = V , WDS2 = open
CC
WDS1 = GND, WDS2 = V
WDS1 = open, WDS2 = V
CC
CC
WDS1 = WDS2 = V (watchdog disabled)
CC
POWER FꢁIL
0.65 x
0.85 x
V
CC
Power-Fail Select Threshold
V
PFI input
V
V
SEL
V
CC
V
Monitoring Threshold
CC
V
V
V
rising
falling
4.06
1.0
0.9
1.0
4.38
2
4.60
4.0
1.4
8.0
ITH
CC
CC
(Internal Threshold)
Internal Threshold Hysteresis
V
%V
ITH
IHYST
PFI Monitoring Threshold
(External Threshold)
V
PFI rising
PFI falling
1.1
3.5
V
ETH
External Threshold Hysteresis
V
%V
ETH
EHYST
Note 1: All parameters are tested at T = +25°C. Specifications over temperature are guaranteed by design.
A
Note 2: Guaranteed by design. Not production tested.
_______________________________________________________________________________________
3
System Monitoring Oscillator with
Watchdog and Power Fail
Typical Operating Characteristics
(Typical Application Circuit, V
= +5V, T = +25°C, unless otherwise noted.)
A
CC
FREQUENCY vs. SUPPLY VOLTAGE
FREQUENCY vs. TEMPERATURE
DUTY CYCLE vs. SUPPLY VOLTAGE
1.020
1.010
1.000
0.990
0.980
1.040
1.030
1.020
1.010
1.000
0.990
0.980
52
51
50
49
48
NORMALIZED TO V = +5V
CC
V
= +2.9V
V
TH+
= +2.9V
TH+
NORMALIZED TO T = +25°C
A
2.90
3.55
4.20
(V)
4.85
5.50
-40 -25 -10
5
20 35 50 65 80 95 110 125
2.90
3.55
4.20
(V)
4.85
5.50
V
TEMPERATURE (°C)
V
CC
CC
CLOCK OUTPUT WAVEFORM
CLOCK OUTPUT WAVEFORM
WITH C = 10pF
WITH C = 50pF
DUTY CYCLE vs. TEMPERATURE
L
L
MAX7387/88 toc05
MAX7387/88 toc06
52
51
50
49
48
V
CC
= +3.3V
V
CC
= +3.3V
CLOCK
1V/div
CLOCK
1V/div
40ns/div
40ns/div
-40 -25 -10
5
20 35 50 65 80 95 110 125
TEMPERATURE (°C)
CLOCK OUTPUT WAVEFORM
WITH C = 100pF
SUPPLY CURRENT vs. TEMPERATURE
SUPPLY CURRENT vs. SUPPLY VOLTAGE
L
MAX7387/88 toc07
5
4
3
2
1
5
4
3
2
1
V
= 5V
CC
CLOCK
1V/div
V
= 3.3V
CC
V
= 2.9V
TH+
40ns/div
-40 -25 -10
5
20 35 50 65 80 95 110 125
TEMPERATURE (°C)
2.90
3.55
4.20
(V)
4.85
5.50
V
CC
±
_______________________________________________________________________________________
System Monitoring Oscillator with
Watchdog and Power Fail
Typical Operating Characteristics (continued)
(Typical Application Circuit, V
= +5V, T = +25°C, unless otherwise noted.)
A
CC
MAXIMUM V TRANSIENT DURATION
CC
vs. RESET THRESHOLD OVERDRIVE
CLOCK SETTLING TIME FROM START
POWER-ON RESET BEHAVIOR
MAX7387/88 toc10
MAX7387/88 toc11
1000
100
10
V
CC
V
2V/div
CC
2V/div
RESET OCCURS ABOVE THIS CURVE
CLOCK
5V/div
CLOCK
2V/div
t
RST
RST
5V/div
PFO
5V/div
V
CC
FALLING FROM V + 100mV
TH+
PFI = V
CC
1
100 200 300 400 500 600 700 800 900 1000
RESET THRESHOLD OVERDRIVE (mV)
1µs/div
100µs/div
RESPONSE OF RST AND WDO
WDI EXCEEDING t
RISING THRESHOLD vs. TEMPERATURE
WDG
MAX7387/88 toc13
2.90
2.88
2.86
2.84
2.82
2.80
WDI
2V/div
WDO
5V/div
t
WDG
RST
5V/div
t
RST
2ms/div
-40 -25 -10
5
20 35 50 65 80 95 110 125
TEMPERATURE (°C)
_______________________________________________________________________________________
5
System Monitoring Oscillator with
Watchdog and Power Fail
Pin Description
PIN
NꢁME
FUNCTION
MꢁX73ꢃ7 MꢁX73ꢃꢃ
Power-Fail Input. PFI monitors the condition of either an external supplied voltage or V
See the Power Fail section for more details.
.
CC
1
2
3
1
PFI
Power Input. Connect V
to the power supply. Bypass V to GND with a 1µF capacitor.
CC
CC
V
CC
Install the bypass capacitor as close to the device as possible.
Watchdog Timeout Select Input 1. Connect WDS1 and WDS2 to V , GND, or V /2, as
CC
CC
2
WDS1
shown in Table 1, to set the watchdog timeout period.
Watchdog Timeout Select Input 2. Connect WDS2 and WDS1 to V , GND, or V /2, as
shown in Table 1, to set the watchdog timeout period.
Ground
CC
CC
4
5
6
3
4
WDS2
GND
Watchdog Output. Open-drain watchdog output asserts low if WDI is not toggled within the
watchdog timeout period.
WDO
Power-Fail Output. Open-drain output asserts when the voltage being monitored drops below
the power-fail threshold voltage.
7
8
5
6
PFO
Watchdog Input. A rising edge on WDI resets the watchdog timer. If WDI does not receive a
rising edge within the watchdog timeout period (t
), RST/RST asserts. The watchdog
WDG
WDI
timeout period is programmable through WDS1 and WDS2. Connect WDS1 and WDS2 to
to disable watchdog timer.
V
CC
Reset Output. Reset output is available in one of three configurations: push-pull RST,
push-pull RST, or open-drain RST. The reset output occurs if any combination of the following
9
7
8
RST/RST conditions occurs: reset output is asserted during power-up and whenever V is below the
CC
reset threshold level; for devices with WDI, reset output asserts when WDI does not receive a
rising edge within the watchdog timeout period.
10
CLOCK
Clock Output
The integrated reset and watchdog functions provide
the power-supply monitoring functions necessary to
ensure correct microcontroller operation. The reset cir-
cuit has built-in power-supply transient immunity and
provides both power-on reset and power-fail or
brownout reset functionality. Two standard factory-
trimmed reset levels are available. The watchdog timer
is programmable to eight individual timeout values and
may be disabled for test purposes.
Detailed Description
The MAX7387/MAX7388 replace ceramic resonators,
crystals, and supervisory functions for microcontrollers
in 3.3V and 5V applications.
The MAX7387/MAX7388 provide a clock source together
with integrated reset, watchdog, and power-fail func-
tions. The watchdog timer is pin programmable and pro-
vides watchdog timeout values in the 16ms to 2048ms
range. The power-fail output provides early warning of
power failure. The power-fail threshold on the MAX7388
is internally set. The MAX7387 features a programmable
power-fail threshold, which is configurable to detect
A power-fail function is provided for power-supply volt-
age monitoring and can provide advance notice of an
impending power failure. Parts with power-fail input
(MAX7387) monitor external power-supply voltages
through an external resistive divider. Connect PFI to
either an external voltage or the V
supply voltage to
CC
the device. The MAX7387 also provides a separate
watchdog output that is used as a status indicator or to
control safety-critical system elements.
V
to monitor V
.
CC
CC
6
_______________________________________________________________________________________
System Monitoring Oscillator with
Watchdog and Power Fail
Upon completion of the reset timeout, the reset output
is released. See Figure 1.
Clock Output (CLOCK)
The push-pull clock output (CLOCK) drives a ground-
connected 1kΩ load or a positive supply connected
500Ω load to within 300mV of either supply rail. CLOCK
remains stable over the full operating voltage range and
does not generate short output cycles during either
power-on or power-off. A typical startup characteristic is
shown in the Typical Operating Characteristics section.
Low-Voltage Lockout
The reset output asserts whenever V
drops below the
CC
reset falling threshold, V . The difference between the
TH-
reset rising and falling threshold values is V
- (V ).
TH-
TH+
The nominal hysteresis value is 2% of the reset rising
threshold value. The reset detection circuitry provides
filtering to prevent triggering on negative voltage
Reset
The reset function drives the microcontroller reset input
to prevent operation in the cases of the initial power-on
setting, low power-supply voltages, and the failed
watchdog operations. Three reset output versions are
available: push-pull RST, push-pull RST, and open-drain
spikes. See the Maximum V
Transient Duration vs.
CC
Reset Threshold Overdrive typical operating circuit.
Figure 1 shows the reset output (RST/RST) behavior
during power-up and brownout.
RST. The reset timeout period (t ) is nominally 135s.
RST
Watchdog
The watchdog function provides microprocessor moni-
toring by requiring the microprocessor to toggle an out-
put pin to indicate correct operation. The WDI input
monitors the port signal and resets the watchdog timer
on receipt of a rising edge. If an edge is not received
within the required watchdog timeout period, the watch-
dog circuit initiates a reset cycle. The internal watchdog
Power-On Reset (POR)
The internal power-on reset (POR) circuit detects the
power-supply voltage (V ) level at startup. The POR
CC
circuit starts the oscillator when V
exceeds the reset
CC
rising threshold level (V
). The reset output remains
TH+
CC
asserted from the time V
crosses the V
and con-
TH+
tinues to be asserted for the reset timeout period (t
).
RST
5
V
ITH
V - V
ITH IHYST
4
3
2
1
V
TH+
V
TH-
V
CCR
CLK
RST
t
RST
PFO
CLOCK STARTS ON INTERNAL
POR (V , V RISING)
TH+ CC
RST RELEASES AFTER THE
RESET TIMEOUT PERIOD
PFO ASSERTS AS V DROPS
CC
ITH IHYST
BELOW V - V
RST ASSERTS ON RESET FALLING
VOLTAGE (V , V FALLING);
TH- CC
CLOCK STOPS
RST CONTINUES TO
ASSERT UNTIL V
CCR
Figure 1. RST/RST and PFO Behavior During Power-Up and Brownout
_______________________________________________________________________________________
7
System Monitoring Oscillator with
Watchdog and Power Fail
circuits are reset and the watchdog timer restarts at the
MAX7387 Power Fail
Internal (V ) detection is configured by connecting
end of the reset cycle (RST/RST output releases).
CC
PFI to V . The internal V
rising threshold (V ) is
CC
CC
ITH
For the MAX7387, the WDO output asserts if the WDI
input does not receive a rising edge within the watchdog
timeout period. WDO output remains asserted until a
valid edge is received on the WDI input, signifying cor-
rect microprocessor operation. The WDO output can be
used as a status indicator either to the microprocessor
or to an external device, such as a fault-indicating LED
or sounder. The WDO output is an open-drain output.
The power-up condition of the WDO output is high
(not asserted).
set at 4.38V. The open-drain PFO asserts low if the V
CC
supply voltage drops below the V
falling threshold
CC
value (V
). The V
falling threshold is nominally
HYST
2% below the V
CC
rising threshold.
CC
Applications Information
Interfacing to a Microcontroller
Clock Input
The CLOCK output is a push-pull, CMOS logic output,
which directly drives any microprocessor (µP) or micro-
controller (µC) clock input. There are no impedance-
The operation of the watchdog and reset function is
illustrated in Figure 2.
The watchdog timeout period is set to one of nine possible
values by pin strapping WDS1 and WDS2. Each control
input has three possible values assigned by connection
to GND, V , or V /2 (see Table 1). One of the
Table 1. Watchdog Timeout Periods
WꢁTCHDOG TIMEOUT
PERIOD (ms)
CC
CC
WDS1
WDS2
assigned values disables the watchdog function and is
intended for customer use during test. The watchdog
timer is disabled while the RST/RST output is asserted.
MIN
11
TYP
16
MꢁX
22
GND
GND
GND
GND
V
V
V
/2 = open
22
32
44
CC
CC
CC
Power Fail
V
44
64
88
CC
MAX7388 Power Fail
The power-fail function provides early warning of a power
failure. The power-fail comparator threshold is internally
GND
V
V
V
/2 = open
/2 = open
/2 = open
88
128
177
354
708
1416
2832
CC
CC
CC
/2 = open
177
354
708
1416
256
V
512
CC
set to 4.38V V
rising threshold (V ). The open-drain
ITH
CC
PFO asserts low if the V
supply voltage drops below
GND
V
1024
2048
Disabled
CC
CC
the V
falling threshold value. The V
falling threshold
CC
CC
/2 = open
V
V
CC
CC
is nominally 2% below the V rising threshold.
CC
V
CC
Note: WDS1 or WDS2 is pulled to open if left floating.
V
CC
CLK
RST
RESET TIMEOUT PERIOD
(t
)
RST
ACTIVE
INTERNAL
WATCHDOG STATE
TRIPPED
WDI
WDO
WATCHDOG TIMEOUT
PERIOD (t
)
WDG
Figure 2. Watchdog Timing Diagram
_______________________________________________________________________________________
ꢃ
System Monitoring Oscillator with
Watchdog and Power Fail
matching issues when using the MAX7387/MAX7388.
load. Use a bypass capacitor value of at least 1000
times that of the output load capacitance.
Operate the MAX7387/MAX7388 and microcontroller
(or other clock input device) from the same supply volt-
age level. Refer to the microcontroller data sheet for
clock-input compatibility with external clock signals.
Output Jitter
The MAX7387/MAX7388s’ jitter performance is given in
the Electrical Characteristics table as a peak-to-peak
value obtained by observing the output of the device for
20s with a 500MHz oscilloscope. Jitter measurements
are approximately proportional to the period of the out-
put frequency of the device. Thus, a 4MHz part has
approximately twice the jitter value of an 8MHz part.
The MAX7387/MAX7388 require no biasing compo-
nents or load capacitance. When using the MAX7387/
MAX7388 to retrofit a crystal oscillator, remove all bias-
ing components from the oscillator input.
Power-Supply Consideration
The MAX7387/MAX7388 operate with power-supply
voltages in the 2.7V to 5.5V range. Power-supply
decoupling is needed to maintain the power-supply
rejection performance of the MAX7387/MAX7388.
The jitter performance of all clock sources degrades in
the presence of mechanical and electrical interference.
The MAX7387/MAX7388 are immune to vibration,
shock, and EMI influences, and thus provide a consid-
erably more robust clock source than crystal- or ceram-
ic-resonator-based oscillator circuits.
Bypass V
to GND with a 0.1µF surface-mount ceramic
CC
capacitor. Mount the bypass capacitor as close to the
device as possible. If possible, mount the MAX7387
/MAX7388 close to the microcontroller’s decoupling
capacitor so that additional decoupling is not required.
Table 3. Reset Output Type
OUTPUT TYPE
s
A
B
C
A larger-value bypass capacitor is recommended if the
MAX7387/MAX7388 are to operate with a large capacitive
Push-pull RST
Push-pull RST
Open-drain RST
Table 2. POR Voltage
Note: Standard values are shown in bold. Contact factory for
other output types.
POWER-ON RESET VOLTꢁGE (V
)
r
M
J
TH
±.3ꢃ
3.96
3.44
3.34
3.13
2.ꢃ9
2.82
2.5
Table ±. Clock Output Frequency
CLOCK FREQUENCY (ꢂ
N
P
Q
S
V
X
) (MHz)
ꢂꢂ
CLOCK
4
8
RD
TP
12
16
VB
WB
Note: Contact factory for other frequencies.
Note: Standard values are shown in bold. Contact factory for
other POR voltages.
Selector Guide
FREQUENCY
RꢁNGE (MHz) FUNCTION
RESET
WꢁTCHDOG INPUT (WDI)/
WꢁTCHDOG OUTPUT (WDO)
POWER-FꢁIL INPUT (PFI)/
POWER-FꢁIL OUTPUT (PFO)
PIN-
PꢁCKꢁGE
PꢁRT
SPEED
MAX7387
MAX7388
MAX7389
MAX7390
MAX7391
1 to 16
1 to 16
1 to 16
1 to 16
1 to 16
Yes
Yes
Yes
Yes
Yes
Yes/yes
Yes/no
Yes/yes
Yes/no
—
Yes/yes
No/yes
—
—
—
10 µMAX
8 µMAX
8 µMAX
8 µMAX
8 µMAX
—
—
Yes
Yes
Yes/yes
Note: Other versions with different features are available. Refer to the MAX7389/MAX7390 and MAX7391 data sheets.
_______________________________________________________________________________________
9
System Monitoring Oscillator with
Watchdog and Power Fail
Functional Diagram
RST/RST
MAX7387
MAX7388
PRESCALER
RESET TIMER
POWER-ON
RESET
OSCILLATOR
CLOCK
WDO*
WATCHDOG
TIMER
WDI
N
WDS1
WDS2
PFI*
PFO
INTERNAL (V DETECTION)
CC
N
V_TH
*MAX7387 ONLY
GND
Typical Application Circuit
POWER
SUPPLY
5V
DC-DC
V
CC
WDS1
WDS2
RST/RST
INT
RST/RST
R1
PFO
WDI
MAX7387
MAX7388
µC
I/O PORT
I/O PORT
PFI*
WDO*
R2
OSC1
CLOCK
GND
*MAX7387 ONLY
Chip Information
PROCESS: BICMOS
1ꢀ ______________________________________________________________________________________
System Monitoring Oscillator with
Watchdog and Power Fail
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
4X S
8
8
MILLIMETERS
INCHES
DIM MIN
MAX
MAX
MIN
-
-
0.043
0.006
0.037
0.014
0.007
0.120
1.10
0.15
0.95
0.36
0.18
3.05
A
0.002
0.030
0.010
0.005
0.116
0.05
0.75
0.25
0.13
2.95
A1
A2
b
E
H
Ø0.50 0.1
c
D
e
0.0256 BSC
0.65 BSC
0.6 0.1
E
H
0.116
0.188
0.016
0°
0.120
2.95
4.78
0.41
0°
3.05
5.03
0.66
6°
0.198
0.026
6°
L
1
1
α
S
0.6 0.1
0.0207 BSC
0.5250 BSC
BOTTOM VIEW
D
TOP VIEW
A1
A2
A
c
α
e
L
b
SIDE VIEW
FRONT VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, 8L uMAX/uSOP
APPROVAL
DOCUMENT CONTROL NO.
REV.
1
21-0036
J
1
______________________________________________________________________________________ 11
System Monitoring Oscillator with
Watchdog and Power Fail
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
e
4X S
10
10
INCHES
MAX
MILLIMETERS
MAX
1.10
0.15
0.95
3.05
3.00
3.05
3.00
5.05
0.70
DIM MIN
MIN
-
A
-
0.043
0.006
0.037
0.120
0.118
0.120
0.118
0.199
A1
A2
D1
D2
E1
E2
H
0.002
0.030
0.116
0.114
0.116
0.114
0.187
0.05
0.75
2.95
2.89
2.95
2.89
4.75
0.40
H
Ø0.50 0.1
0.6 0.1
L
0.0157 0.0275
0.037 REF
L1
b
0.940 REF
0.007
0.0106
0.177
0.270
0.200
1
1
e
0.0197 BSC
0.500 BSC
0.6 0.1
c
0.0035 0.0078
0.0196 REF
0.090
BOTTOM VIEW
0.498 REF
S
α
TOP VIEW
0°
6°
0°
6°
D2
E2
GAGE PLANE
A2
c
A
E1
b
L
α
A1
D1
L1
FRONT VIEW
SIDE VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, 10L uMAX/uSOP
APPROVAL
DOCUMENT CONTROL NO.
REV.
1
21-0061
1
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.
12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2006 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.
ENGL ISH • ? ? ? ? • ? ? ? • ? ? ?
WH AT 'S NEW
PR OD UC TS
SO LUTI ONS
D ES IG N
A PPNOTES
SU PPORT
B U Y
COM PA N Y
M EMB ERS
M A X 7 3 8 7
Pa rt Nu m ber T abl e
N o t e s :
1 . S e e t h e M A X 7 3 8 7 Q u i c k V i e w D a t a S h e e t f o r f u r t h e r i n f o r m a t i o n o n t h i s p r o d u c t f a m i l y o r d o w n l o a d t h e
M A X 7 3 8 7 f u l l d a t a s h e e t ( P D F , 6 0 8 k B ) .
2 . O t h e r o p t i o n s a n d l i n k s f o r p u r c h a s i n g p a r t s a r e l i s t e d a t : h t t p : / / w w w . m a x i m - i c . c o m / s a l e s .
3
.
D
i
d
n
'
t
F
i
n
d
W
h
a
t
Y
o
u
N
e
e
d
?
A
s
k
o
u
r
a
p
p
l
i
c
a
t
i
o
n
s
e
n
g
i
n
e
e
r
s
.
E
x
p
e
r
t
a
s
s
i
s
t
a
n
c
e
i
n
f
i
n
d
i
n
g
p
a
r
t
s
,
u
s
u
a
l
l
y
w
i
t
h
i
n
o n e b u s i n e s s d a y .
4 . P a r t n u m b e r s u f f i x e s : T o r T & R = t a p e a n d r e e l ; + = R o H S / l e a d - f r e e ; # = R o H S / l e a d - e x e m p t . M o r e : S e e f u l l
d a t a s h e e t o r P a r t N a m i n g C o n v e n t i o n s .
5 . * S o m e p a c k a g e s h a v e v a r i a t i o n s , l i s t e d o n t h e d r a w i n g . " P k g C o d e / V a r i a t i o n " t e l l s w h i c h v a r i a t i o n t h e p r o d u c t
u s e s .
P a r t N u m b e r
F r e e
S a m p l e
B u y
D i r e c t
T e m p
R o H S / L e a d - F r e e ?
M a t e r i a l s A n a l y s i s
P a c k a g e : T Y P E P I N S S I Z E
D R A W I N G C O D E / V A R *
M A X 7 3 8 7 C M A C
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M A X 7 3 8 7 C S A C
M A X 7 3 8 7 C M V B - T
M A X 7 3 8 7 C M T P
M A X 7 3 8 7 C M R D
M A X 7 3 8 7 C M T P - T
M A X 7 3 8 7 C M R D - T
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M A X 7 3 8 7 C S W B - T
M A X 7 3 8 7 C S V B - T
M A X 7 3 8 7 C S T P - T
M A X 7 3 8 7 C S R D - T
M A X 7 3 8 7 C M W B
M A X 7 3 8 7 C S W B
M A X 7 3 8 7 C S V B
M A X 7 3 8 7 C S T P
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
M A X 7 3 8 7 C S R D
M A X 7 3 8 7 C M W B - T
M A X 7 3 8 7 C M V B
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
u M A X ; 1 0 p i n ; 3 x 3 m m
D w g : 2 1 - 0 0 6 1 I ( P D F )
- 4 0 C t o + 1 2 5 C R o H S / L e a d - F r e e : N o
M a t e r i a l s A n a l y s i s
U s e p k g c o d e / v a r i a t i o n : U 1 0 - 2 *
D i d n ' t F i n d W h a t Y o u N e e d ?
C O N T A C T U S : S E N D U S A N E M A I L
C o p y r i g h t 2 0 0 7 b y M a x i m I n t e g r a t e d P r o d u c t s , D a l l a s S e m i c o n d u c t o r • L e g a l N o t i c e s • P r i v a c y P o l i c y
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