Page 1
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General Description
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
White Goods
Automotive
Consumer Products
Appliances and Controls
Handheld Products
Portable Equipment
Microcontroller Systems
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: 80ps
P-P
at 16MHz
♦ 4mA Operating Current at 16MHz
♦ -40°C to +125°C Temperature Range
♦ Small 5-Pin SOT23 Package
MAX7382
Silicon Oscillator with Reset Output
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
OSC1
OSC2
RST
µC
GND
RST/RST
CLOCK
E.C.
V
CC
0.1µF
V
CC
2.7V TO 5.5V
MAX7382
Typical Operating Circuit
19-3491; Rev 0; 1/05
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.
*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.
Pin Configuration appears at end of data sheet.
PART* TEMP RANGE
MAX7382A_ _ _-T -40°C to +125°C 5 SOT23-5
MAX7382B_ _ _-T -40°C to +125°C 5 SOT23-5
MAX7382C_ _ _-T -40°C to +125°C
PINPACKAGE
5 SOT23-5 Open drain
RESET
OUTPUT
Active-high
push-pull
Active-low
push-pull
Page 2
MAX7382
Silicon Oscillator with Reset Output
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
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.
VCCto GND...........................................................-0.3V to +6.0V
All Other Pins to GND...................................-0.3V to (V+ + 0.3V)
CLOCK, RST Current .......................................................±50mA
Continuous Power Dissipation (T
A
= +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
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)
Operating Supply Voltage V
Operating Supply Current I
CLOCK OUTPUT
Output High Voltage V
Output Low Voltage V
Clock Frequency Accuracy f
Clock Temperature Coefficient TA = -40°C to +125°C ±50 ±350 ppm/°C
Duty Cycle (Note 2) 40 50 60 %
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
CC
f
= 16MHz, TA = -40°C to +125°C,
CLOCK
no load
f
= 14.7456MHz, TA = -40°C to
CLOCK
+125°C, no load
f
= 12MHz, TA = -40°C to +125°C,
CC
OH
OL
CLOCK
CLOCK
no load
f
= 11.0592MHz, TA = -40°C to
CLOCK
+125°C, no load
f
= 10MHz, TA = -40°C to +125°C,
CLOCK
no load
VL = 4.5V, I
VL = 2.7V, I
VL = 4.5V, I
VL = 2.7V, I
VCC = 5V, TA = +25°C, deviation from
selected frequency
VCC = 2.7V to 5.5V, TA = +25°C,
deviation from selected frequency
SOURCE
SOURCE
SINK
SINK
2.7 5.5 V
8.7
8.0
6.5
6.0
5.4
= 7.0mA
= 2.0mA
= 20mA
= 10mA
- 0.4 V
V
L
0.4 V
-2.5 +2.5
-5.0 +3.5
mA
%
Page 3
MAX7382
Silicon Oscillator with Reset Output
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(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)
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.
Output Jitter
Output Rise Time t
Output Fall Time t
Power-On-Reset Threshold V
Reset Hysteresis HYST
Power-On-Reset Delay POR
RESET OUTPUT
Output High Voltage
(Note 3)
Output Low Voltage V
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
R
F
TH
DLYVCC
V
OH
OL
Observation of 16MHz for 20s using a
12GHz oscilloscope
10% to 90% 5 ns
90% to 10% 5 ns
VCC rising, deviation
from nominal threshold
Difference between rising and falling
thresholds
rising from 0 to 5V in 1µs at +25°C 122 µs
VL = 4.5V, I
VL = 2.7V, I
VL = 4.5V, I
VL = 2.7V, I
SOURCE
SOURCE
= 20mA 0.4
SINK
SOURCE
TA = +25°C -2 +2
T
= -40°C to
A
+125°C
= 7.0mA
= 2.0mA
= 10mA 0.4
-5 +5
V
CC
0.4
V
CC
0.4
80 ps
1%
-
-
P-P
%
V
V
Page 4
MAX7382
Silicon Oscillator with Reset Output
4 _______________________________________________________________________________________
Typical Operating Characteristics
(VCC= VL= 5V, TA= +25°C, frequency = 10MHz, unless otherwise noted.)
48.0
48.5
49.5
49.0
50.0
50.5
-55 21-17 59 97 135
DUTY CYCLE vs. TEMPERATURE
MAX7382 toc01
TEMPERATURE (°C)
DUTY CYCLE (%)
FREQUENCY = 10MHz
DUTY CYCLE
vs. SUPPLY VOLTAGE
MAX7382 toc02
SUPPLY VOLTAGE (V)
DUTY CYCLE (%)
5.14.74.33.93.53.1
46
47
48
49
50
51
45
2.7 5.5
FREQUENCY = 11.0592MHz
2.90
3.00
2.95
3.10
3.05
3.20
3.15
3.25
-55 21 59-17 97 135
SUPPLY CURRENT vs. TEMPERATURE
MAX7382 toc03
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
FREQUENCY = 10MHz
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX7382 toc04
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
5.14.74.33.93.53.1
2.0
2.5
3.0
3.5
4.0
1.5
2.7 5.5
FREQUENCY = 11.0592MHz
FREQUENCY DEVIATION
vs. SUPPLY VOLTAGE
MAX7382 toc05
SUPPLY VOLTAGE (V)
FREQUENCY DEVIATION (%)
5.14.73.1 3.5 3.9 4.3
-1.5
-1.0
-0.5
0
0.5
1.0
1.5
2.0
-2.0
2.7 5.5
FREQUENCY = 11.0592MHz
FREQUENCY DEVIATION
vs. TEMPERATURE
MAX7382 toc06
TEMPERATURE (°C)
FREQUENCY DEVIATION (%)
9759-17 21
-3
-2
-1
0
1
2
3
4
-4
-55 135
FREQUENCY = 10MHz
CHANNEL 1 = CLOCK, CHANNEL 2 = V
CC
10µs/div
SETTLING TIME FROM START
MAX7382 toc07
CH1 FREQ
9.992MHz
LOW RESOLUTION
CLOCK OUTPUT WAVEFORM
(C
L
= 10pF)
MAX7382 toc08
20ns/div
CLOCK OUTPUT WAVEFORM
(C
L
= 10pF)
MAX7382 toc09
20ns/div
Page 5
MAX7382
Silicon Oscillator with Reset Output
_______________________________________________________________________________________ 5
Typical Operating Characteristics (continued)
(VCC= VL= 5V, TA= +25°C, frequency = 10MHz, unless otherwise noted.)
Pin Description
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.
CLOCK OUTPUT WAVEFORM
= 100pF)
(C
L
20ns/div
MAX7382 toc10
MAXIMUM TRANSIENT DURATION (s)
MAXIMUM TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
1
0.1
0.01
1m
10m
100m
1µ
0.04 0.24
RESET THRESHOLD OVERDRIVE (V)
0.09
V
RESET
0.14
= 4.32V
0.19
MAX7382 toc11
PIN NAME FUNCTION
1 CLOCK Push-Pull Clock Output
2 GND Ground
3 RST Reset Output. Open-drain or push-pull output. See the Ordering Information.
4VCCPositive Supply Voltage. Bypass with a 0.1µF capacitor to GND.
5 E.C. Externally Connected. Connect to Vcc.
SUPPLY CURRENT
vs. FREQUENCY
5
4
3
SUPPLY CURRENT (mA)
2
1
10 16
FREQUENCY (MHz)
MAX7382 toc12
1514131211
Page 6
MAX7382
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.
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 V
TH-
threshold
and remains asserted for 120µs after the monitored input
exceeds the internal V
TH+
threshold. The open-drain
RST output requires an external pullup resistor.
Output Jitter
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.
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.
Silicon Oscillator with Reset Output
6 _______________________________________________________________________________________
Figure 1. Functional Diagram
Table 1. Standard Reset Threshold
Levels
Table 2. Standard Frequencies
Contact factory for nonstandard reset threshold options.
For all other frequency options, contact factory.
Table 3. Standard Part Numbers
*Contact factory for availability.
2.7V TO 5.5V
V
CC
MAX7382
OSCILLATOR
POR
RST
CLOCK
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
SUFFIX STANDARD FREQUENCY (MHz)
UK 10
UT 11.0592
VB 12
VT 14.7456
WB 16
YN 32
PART
MAX7382CRUK 2.89 10 AEVU
MAX7382CRUT* 2.89 11.0592 —
MAX7382CRVB 2.89 12 AEVM
MAX7382CRVT* 2.89 14.7456 —
MAX7382CRWB 2.89 16 AEVK
MAX7382CRYN* 2.89 32 AEVL
MAX7382CMUK* 4.38 10 —
MAX7382CMUT* 4.38 11.0592 —
MAX7382CMVB 4.38 12 AEVJ
MAX7382CMVT* 4.38 14.7456 —
MAX7382CMWB 4.38 16 AEVH
MAX7382CMYN* 4.38 32 AEVI
RESET
THRESHOLD
(V)
FREQUENCY
(MHz)
TOP
MARK
GND
Page 7
MAX7382
Silicon Oscillator with Reset Output
_______________________________________________________________________________________ 7
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 (V
TH+
).
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.
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
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 VCCto 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.
GND
V
CC
RST
1 5 E.C.CLOCK
MAX7382
SOT23
TOP VIEW
2
34
Pin Configuration
Chip Information
TRANSISTOR COUNT: 2937
PROCESS: BiCMOS
Page 8
Silicon Oscillator with Reset Output
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
.)
SOT-23 5L .EPS
PACKAGE OUTLINE, SOT-23, 5L
1
21-0057
E
1
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