Maxim MAX7382CMUK Silicon oscillator with reset output Datasheet

19-3491; Rev 0; 1/05
Silicon Oscillator with Reset Output
The MAX7382 silicon oscillator replaces ceramic resonators, crystals, and crystal-oscillator modules as the
clock source for microcontrollers in 3V, 3.3V, and 5V
applications. The MAX7382 features a factory-programmed oscillator and a microprocessor (µP) poweron-reset (POR) supervisor.
Unlike typical crystal and ceramic-resonator oscillator
circuits, the MAX7382 is resistant to vibration and EMI.
The high-output-drive current and absence of highimpedance nodes makes the oscillator less susceptible
to dirty or humid operating conditions. With a wide
operating temperature range as standard, the
MAX7382 is a good choice for demanding home appliance and automotive environments.
The MAX7382 is available with factory-programmed frequencies ranging from 10MHz to 32MHz. See Table 2
for standard frequencies and contact the factory for
custom frequencies. Refer to the MAX7376 data sheet
for frequencies less than 10MHz.
The MAX7382 is available in a 5-pin SOT23 package.
The MAX7382 standard operating temperature range is
-40°C to +125°C. See the Applications Information section for extended operating temperature range.
Applications
Features
♦ 2.7V to 5.5V Operation
♦ 10MHz to 32MHz Oscillator
♦ Integrated POR
♦ ±10mA Clock Output Drive Capability
♦ 2.5% Initial Accuracy
♦ ±50ppm/°C Frequency Drift
♦ 50% Duty Cycle
♦ 5ns Output Rise and Fall Time
♦ Low Jitter: 80psP-P at 16MHz
♦ 4mA Operating Current at 16MHz
♦ -40°C to +125°C Temperature Range
♦ Small 5-Pin SOT23 Package
Ordering Information
PART*
TEMP RANGE
PINPACKAGE
RESET
OUTPUT
Active-high
MAX7382A_ _ _-T -40°C to +125°C 5 SOT23-5 push-pull
White Goods
Active-low
MAX7382B_ _ _-T -40°C to +125°C 5 SOT23-5 push-pull
Automotive
MAX7382C_ _ _-T -40°C to +125°C 5 SOT23-5 Open drain
Consumer Products
*Standard version is shown in bold. The first letter after the part
number designates the reset output option. Insert the letter
corresponding to the desired reset threshold level from Table 1
in the next position. Insert the two-letter code from Table 2 in
the remaining two positions for the desired frequency range.
Table 1 and Table 2 are located at the end of the data sheet.
Appliances and Controls
Handheld Products
Portable Equipment
Microcontroller Systems
Typical Operating Circuit
VCC 2.7V TO 5.5V
0.1µF
VCC
CLOCK
OSC1
OSC2
MAX7382
E.C.
RST/RST
RST
µC
GND
Pin Configuration appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
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.
1
MAX7382
General Description
MAX7382
Silicon Oscillator with Reset Output
ABSOLUTE MAXIMUM RATINGS
VCC to GND ...........................................................-0.3V to +6.0V
All Other Pins to GND...................................-0.3V to (V+ + 0.3V)
CLOCK, RST Current .......................................................±50mA
Continuous Power Dissipation (TA = +70°C)
5-Pin SOT23 (derate 7.1mW/°C above +70°C) ....571mW (U5-2)
Operating Temperature Range .........................-55°C to +135°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+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
(Typical Operating Circuit, VCC = 2.7V to 5.5V, VL = VCC, TA = -40°C to +125°C. Typical values are at VCC = 5.0V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
Operating Supply Voltage
Operating Supply Current
SYMBOL
CONDITIONS
VCC
ICC
MIN
TYP
2.7
MAX
UNITS
5.5
V
fCLOCK = 16MHz, TA = -40°C to +125°C,
no load
8.7
fCLOCK = 14.7456MHz, TA = -40°C to
+125°C, no load
8.0
fCLOCK = 12MHz, TA = -40°C to +125°C,
no load
6.5
fCLOCK = 11.0592MHz, TA = -40°C to
+125°C, no load
6.0
fCLOCK = 10MHz, TA = -40°C to +125°C,
no load
5.4
mA
CLOCK OUTPUT
Output High Voltage
VOH
Output Low Voltage
VOL
Clock Frequency Accuracy
fCLOCK
VL = 4.5V, ISOURCE = 7.0mA
VL = 2.7V, ISOURCE = 2.0mA
V
VL = 4.5V, ISINK = 20mA
0.4
VL = 2.7V, ISINK = 10mA
VCC = 5V, TA = +25°C, deviation from
selected frequency
-2.5
+2.5
VCC = 2.7V to 5.5V, TA = +25°C,
deviation from selected frequency
-5.0
+3.5
V
%
Clock Temperature Coefficient
TA = -40°C to +125°C
Duty Cycle
(Note 2)
2
VL - 0.4
40
±50
±350
ppm/°C
50
60
%
_______________________________________________________________________________________
Silicon Oscillator with Reset Output
(Typical Operating Circuit, VCC = 2.7V to 5.5V, VL = VCC, TA = -40°C to +125°C. Typical values are at VCC = 5.0V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Output Jitter
CONDITIONS
MIN
TYP
MAX
UNITS
Observation of 16MHz for 20s using a
12GHz oscilloscope
80
psP-P
Output Rise Time
tR
10% to 90%
5
ns
Output Fall Time
tF
90% to 10%
5
ns
Power-On-Reset Threshold
Reset Hysteresis
VTH
HYST
Power-On-Reset Delay
PORDLY
VCC rising, deviation
from nominal threshold
TA = +25°C
-2
+2
TA = -40°C to
+125°C
-5
+5
Difference between rising and falling
thresholds
VCC rising from 0 to 5V in 1µs at +25°C
%
1
%
122
µs
RESET OUTPUT
Output High Voltage
(Note 3)
Output Low Voltage
VL = 4.5V, ISOURCE = 7.0mA
VCC 0.4
VL = 2.7V, ISOURCE = 2.0mA
VCC 0.4
V
VOH
VOL
VL = 4.5V, ISINK = 20mA
0.4
VL = 2.7V, ISOURCE = 10mA
0.4
V
Note 1: All parameters tested at TA = +25°C. Specifications over temperature are guaranteed by design.
Note 2: Guaranteed by design. Not production tested.
Note 3: For push-pull output only.
_______________________________________________________________________________________
3
MAX7382
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(VCC = VL = 5V, TA = +25°C, frequency = 10MHz, unless otherwise noted.)
DUTY CYCLE
vs. SUPPLY VOLTAGE
FREQUENCY = 10MHz
49.0
48.5
MAX7382 toc02
3.25
3.20
SUPPLY CURRENT (mA)
49.5
FREQUENCY = 11.0592MHz
50
DUTY CYCLE (%)
49
48
47
46
45
48.0
-55
-17
21
59
97
3.10
FREQUENCY = 10MHz
3.05
3.00
2.90
2.7
135
3.15
2.95
3.1
3.5
3.9
4.3
4.7
5.1
5.5
-55
-17
21
59
97
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
FREQUENCY DEVIATION
vs. SUPPLY VOLTAGE
FREQUENCY DEVIATION
vs. TEMPERATURE
3.0
2.5
FREQUENCY = 11.0592MHz
1.5
1.0
0.5
0
-0.5
-1.0
135
4
MAX7382 toc06
3.5
2.0
FREQUENCY = 10MHz
3
FREQUENCY DEVIATION (%)
FREQUENCY = 11.0592MHz
FREQUENCY DEVIATION (%)
MAX7382 toc04
4.0
MAX7382 toc05
DUTY CYCLE (%)
50.0
SUPPLY CURRENT vs. TEMPERATURE
51
MAX7382 toc01
50.5
MAX7382 toc03
DUTY CYCLE vs. TEMPERATURE
SUPPLY CURRENT (mA)
MAX7382
Silicon Oscillator with Reset Output
2
1
0
-1
-2
2.0
-3
-1.5
-4
-2.0
1.5
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
-55
-17
21
59
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
SETTLING TIME FROM START
CLOCK OUTPUT WAVEFORM
(CL = 10pF)
CLOCK OUTPUT WAVEFORM
(CL = 10pF)
20ns/div
20ns/div
CH1 FREQ
9.992MHz
LOW RESOLUTION
10µs/div
135
MAX7382 toc09
MAX7382 toc08
MAX7382 toc07
CHANNEL 1 = CLOCK, CHANNEL 2 = VCC
4
97
SUPPLY VOLTAGE (V)
_______________________________________________________________________________________
Silicon Oscillator with Reset Output
CLOCK OUTPUT WAVEFORM
(CL = 100pF)
MAXIMUM TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
SUPPLY CURRENT (mA)
0.1
0.01
1m
10m
VRESET = 4.32V
4
3
2
100m
1µ
0.04
20ns/div
5
MAX7382 toc11
MAXIMUM TRANSIENT DURATION (s)
1
SUPPLY CURRENT
vs. FREQUENCY
MAX7382 toc12
MAX7382 toc10
1
0.09
0.14
0.19
0.24
10
11
12
RESET THRESHOLD OVERDRIVE (V)
13
14
15
16
FREQUENCY (MHz)
Pin Description
PIN
NAME
1
CLOCK
FUNCTION
2
GND
Push-Pull Clock Output
Ground
3
RST
Reset Output. Open-drain or push-pull output. See the Ordering Information.
4
VCC
Positive Supply Voltage. Bypass with a 0.1µF capacitor to GND.
5
E.C.
Externally Connected. Connect to Vcc.
Detailed Description
The MAX7382 is a clock generator with integrated reset
for microcontrollers (µCs) and UARTs in 3V, 3.3V, and
5V applications. The MAX7382 is a replacement for
crystal-oscillator modules, crystals, or ceramic resonators, and a system reset IC. The clock frequency
and reset threshold voltage are factory trimmed to specific values. A variety of popular standard frequencies
are available; see Table 2. No external components are
required for setting or adjusting the frequency.
Oscillator
The push-pull clock output drives a load to within
400mV of either supply rail. The clock output remains
stable over the full operating voltage range and does
not generate short output cycles during either power-on
or changing of the frequency. A typical oscillating startup is shown in the Typical Operating Characteristics.
_______________________________________________________________________________________
5
MAX7382
Typical Operating Characteristics (continued)
(VCC = VL = 5V, TA = +25°C, frequency = 10MHz, unless otherwise noted.)
MAX7382
Silicon Oscillator with Reset Output
Applications Information
Interfacing to a Microcontroller
Clock Input
The MAX7382 clock output is a push-pull, CMOS, logic
output that directly drives a µP or µC clock input. There
are no impedance-matching issues when using the
MAX7382. Refer to the microcontroller data sheet for
clock input compatibility with external clock signals.
The MAX7382 requires no biasing components or load
capacitance. When using the MAX7382 to retrofit a
crystal oscillator, remove all biasing components from
the oscillator input.
Table 1. Standard Reset Threshold
Levels
SUFFIX
RESET THRESHOLD (V)
X
2.50
V
2.71
R
2.89 standard value
Q
3.13
P
3.34
N
3.44
J
3.96
M
4.38 standard value
Contact factory for nonstandard reset threshold options.
Reset Output
The MAX7382 is available with three reset output stage
options: push-pull active-low, push-pull active-high, and
open-drain active-low. RST is asserted when the monitored input (VCC) drops below the internal VTH- threshold
and remains asserted for 120µs after the monitored input
exceeds the internal VTH+ threshold. The open-drain
RST output requires an external pullup resistor.
Table 2. Standard Frequencies
SUFFIX
STANDARD FREQUENCY (MHz)
UK
10
UT
11.0592
VB
12
Output Jitter
VT
14.7456
The MAX7382’s jitter performance is given in the
Electrical Characteristics table as a peak-to-peak value
obtained by observing the output of the MAX7382 for
20s with a 12GHz oscilloscope. Jitter measurements
are approximately proportional to the period of the output of the device. Thus, a 10MHz device has approximately twice the jitter value of a 20MHz device. The
jitter performance of all clock sources degrades in the
presence of mechanical and electrical interference.
WB
16
YN
32
VCC 2.7V TO 5.5V
MAX7382
POR
OSCILLATOR
GND
RST
CLOCK
For all other frequency options, contact factory.
Table 3. Standard Part Numbers
PART
RESET
THRESHOLD
(V)
FREQUENCY
(MHz)
TOP
MARK
MAX7382CRUK
MAX7382CRUT*
MAX7382CRVB
MAX7382CRVT*
MAX7382CRWB
MAX7382CRYN*
MAX7382CMUK*
MAX7382CMUT*
MAX7382CMVB
MAX7382CMVT*
MAX7382CMWB
MAX7382CMYN*
2.89
2.89
2.89
2.89
2.89
2.89
4.38
4.38
4.38
4.38
4.38
4.38
10
11.0592
12
14.7456
16
32
10
11.0592
12
14.7456
16
32
AEVU
—
AEVM
—
AEVK
AEVL
—
—
AEVJ
—
AEVH
AEVI
*Contact factory for availability.
The MAX7382 is relatively immune to vibration, shock,
and EMI influences and thus provides a considerably
more robust clock source than crystal or ceramic resonator-based oscillator circuits.
Figure 1. Functional Diagram
6
_______________________________________________________________________________________
Silicon Oscillator with Reset Output
Extended Temperature Operation
The MAX7382 was tested to +135°C during product characterization and shown to function normally at this temperature (see the Typical Operating Characteristics).
However, production test and qualification is only performed from -40°C to +125°C at this time. Contact the factory if operation outside this range is required.
Power-Supply Considerations
Pin Configuration
TOP VIEW
CLOCK
1
GND 2
5
E.C.
4
VCC
MAX7382
RST 3
SOT23
Chip Information
TRANSISTOR COUNT: 2937
PROCESS: BiCMOS
The MAX7382 operates with a 2.7V and 5.5V powersupply voltage. Good power-supply decoupling is
needed to maintain the power-supply rejection performance of the MAX7382. Bypass VCC to GND with a
0.1µF surface-mount ceramic capacitor. Mount the
bypassing capacitor as close to the device as possible.
If possible, mount the MAX7382 close to the microcontroller’s decoupling capacitor so that additional decoupling is not required. Use a larger value of bypass
capacitor recommended if the MAX7382 is to operate
with a large capacitive load. Use a bypass capacitor
value of at least 1000 times that of the output load
capacitance.
_______________________________________________________________________________________
7
MAX7382
Initial Power-Up and Operation
An internal power-up reset holds the clock output low
until the supply voltage has risen above the power-onreset threshold (VTH+).
RST holds the microcontroller in a reset condition until
120µs after the clock has started up. This reset delay
ensures that the clock output and the microcontroller’s
internal clock circuits have stabilized before the system
is allowed to start. Typical microcontroller reset delay
ranges from 1ms to 250ms to allow a slow crystal oscillator circuit to start up. The MAX7382 has a fast startup,
eliminating the need for such a long reset delay.
Silicon Oscillator with Reset Output
SOT-23 5L .EPS
PACKAGE OUTLINE, SOT-23, 5L
21-0057
E
1
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.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2005 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.
MAX7382
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.)
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