19-3060; Rev 2; 7/04
3-Pin Silicon Oscillator
General Description
The MAX7375 is a silicon oscillator, intended as a low-
cost improvement replacing ceramic resonators, crys-
tals, and crystal oscillator modules used as the clock
source for microcontrollers and UARTs in 3V, 3.3V, and
5V applications.
The MAX7375 is a fully integrated oscillator, supplied at
specific factory-trimmed frequencies with a Rail-to-
Rail® 50% duty cycle square-wave output. The oscilla-
tor frequency is generated directly without the use of a
phase-locked loop (PLL). No additional components
are used to set or adjust the frequency.
Unlike typical crystal and ceramic resonator oscillator
circuits, the MAX7375 is highly resistant to vibration
and EMI. The high output drive current and absence of
high-impedance nodes also makes the oscillator less
susceptible to dirty or humid operating conditions. With
a wide operating temperature range, the oscillator is a
good choice for demanding home appliance and auto-
motive environments.
Available in 3-pin space-saving SC70 and SOT23 pack-
ages, the MAX7375 is offered in standard and nonstan-
dard factory-set frequencies ranging from 600kHz to
9.99MHz. See the MAX7381 data sheet for frequencies
≥10MHz.
The MAX7375’s standard operating temperature
range is -40°C to +125°C. See the
Applications
Information
section for extended operating temperature
range.
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
Features
2.7V to 5.5V Operation
Factory-Trimmed Oscillator (600kHz to 9.99MHz)
No External Components Required
±10mA Output Drive Current
2% Initial Accuracy
±50ppm/°C Temp Drift
Fast Startup Time: 5µs
40% to 60% Maximum Duty Cycle
5ns Output Rise and Fall Time-Low EMI
Very Low EMI Susceptibility-No High-Impedance
Nodes
♦
Very Low Jitter: 160ps
P-P
at 8MHz
♦
Tiny Surface-Mount Package (SC70, SOT23)
♦
-40°C to +125°C Temperature Range
MAX7375
Ordering Information
PART
MAX7375AXR105-T
MAX7375AXR185-T
MAX7375AXR365-T
MAX7375AXR375-T
MAX7375AXR405-T
MAX7375AXR425-T
MAX7375AXR805-T
MAX7375AUR105-T
MAX7375AUR185-T
MAX7375AUR365-T
MAX7375AUR375-T
MAX7375AUR405-T
MAX7375AUR425-T
TEMP RANGE
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
PIN-PACKAGE
3 SC70-3
3 SC70-3
3 SC70-3
3 SC70-3
3 SC70-3
3 SC70-3
3 SC70-3
3 SOT23-3
3 SOT23-3
3 SOT23-3
3 SOT23-3
3 SOT23-3
3 SOT23-3
3 SOT23-3
Applications
White Goods
Automotive
Appliances and Controls
Hand-Held Products
Portable Equipment
Microcontroller Systems
Typical Application Circuit
2.7V TO 5.5V
OSC1
µC
V+
CLOCK
MAX7375AUR805-T
MAX7375
GND
The MAX7375 is available in factory-set frequencies from 600kHz
to 9.99MHz. There are seven standard versions (1MHz, 1.84MHz,
3.58MHz, 3.69MHz, 4MHz, 4.19MHz, and 8MHz, as shown in the
Selector Guide) with a required 2.5k order increment.
Nonstandard frequencies are also available with a required 10k
order increment. For nonstandard versions, contact factory for
availability and ordering information. All versions available in
tape-and-reel only.
OSC2
Pin Configuration and Selector Guide appear at end of data
sheet.
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd,
________________________________________________________________
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.
3-Pin Silicon Oscillator
MAX7375
ABSOLUTE MAXIMUM RATINGS
V+ to GND ................................................................-0.3V to +6V
CLOCK to GND ............................................-0.3V to (V+ + 0.3V)
Continuous Power Dissipation (T
A
= +70°C)
3-Pin SC70 (derate 2.9mW/°C over +70°C) .................235mW
3-Pin SOT23 (derate 4mW/°C over +70°C ...................320mW
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
(V+ = 2.7V to 5.5V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V+ = 5V, T
A
= +25°C, unless otherwise noted.)
(Note 1)
PARAMETER
Operating Supply Voltage
SYMBOL
V+
MAX7375A_R105
Operating Supply Current
I+
MAX7375A_R185
MAX7375A_R405
MAX7375A_R805
Output High Voltage
Output Low Voltage
V
OH
V
OL
V+
≥
2.7V, I
SOURCE
= 2.5mA
V+
≥
4.5V, I
SOURCE
= 9mA
V+
≥
2.7, I
SINK
= 10mA
V+
≥
4.5V, I
SINK
= 20mA
V+ = 3.0V,
T
A
= +25°C (Note 2)
V+ = 2.7V to 5.5V,
T
A
= +25°C (Note 2)
(Note 3)
(Note 3)
Observation for 20s using a 500MHz
oscilloscope (MAX7375A_R805)
t
R
t
F
(Note 3)
(Note 3)
45
MAX7375A_R_ _ _
MAX7375A_R_ _ _
-2
-4
±50
52
160
5.0
2.5
V+ - 0.4
V+ - 0.4
0.4
0.4
+2
%
+4
±325
57
ppm/°C
%
ps
P-P
ns
ns
CONDITIONS
MIN
2.7
0.55
0.8
1.7
3.2
TYP
MAX
5.5
1.1
1.25
4.2
6.4
V
V
mA
UNITS
V
Initial CLOCK Frequency
Accuracy
f
CLOCK
CLOCK Frequency Temperature
Sensitivity
Duty Cycle
Output Jitter
Output Rise Time
Output Fall Time
Note 1:
All parameters are tested at T
A
= +25°C. Specifications over temperature are guaranteed by design and characterization.
Note 2:
Typical frequencies are nominal values.
Note 3:
Guaranteed by design and characterization. Not production tested.
2
_______________________________________________________________________________________
3-Pin Silicon Oscillator
MAX7375
Typical Operating Characteristics
(V+ = 5V, T
A
= +25°C, C
L
= 10pF, 8MHz output, unless otherwise noted.)
DUTY CYCLE vs. TEMPERATURE
MAX7375 toc01
DUTY CYCLE vs. SUPPLY VOLTAGE
MAX7375 toc02
SUPPLY CURRENT vs. TEMPERATURE
3.5
SUPPLY CURRENT (mA)
3.0
2.5
2.0
1.5
1.0
0.5
V+ = 2.7V
V+ = 3.3V
V+ = 5V
MAX7375 toc03
55
54
53
DUTY CYCLE (%)
52
51
50
49
48
47
46
45
55
4.0
53
DUTY CYCLE (%)
51
49
47
45
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
2.7
3.4
4.1
4.8
5.5
SUPPLY VOLTAGE (V)
0
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX7375 toc04
FREQUENCY vs. SUPPLY VOLTAGE
MAX7375 toc05
FREQUENCY vs. TEMPERATURE
1.015
NORMALIZED FREQUENCY
1.010
1.005
1.000
0.995
0.990
0.985
0.980
MAX7375 toc06
4.0
3.5
SUPPLY CURRENT (mA)
3.0
2.5
2.0
1.5
1.0
2.7
3.4
4.1
4.8
1.002
1.000
NORMALIZED FREQUENCY
0.998
0.996
0.994
0.992
0.990
1.020
5.5
2.7
3.4
4.1
4.8
5.5
-40
-15
10
35
60
85
110
135
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
SUPPLY CURRENT vs. FREQUENCY
3.5
SUPPLY CURRENT (mA)
3.0
2.5
2.0
V+ = 3.3V
1.5
1.0
0.5
0
0.5
2.5
4.5
FREQUENCY (MHz)
6.5
8.5
V+ = 2.7V
V+ = 5V
MAX7375 toc07
SETTLING TIME FROM START
MAX7375 toc08
4.0
V+ = 5.5V
CLOCK OUTPUT WAVEFORM
WITH C
L
= 10pF
MAX7375 toc09
CLOCK
2V/div
V+
2V/div
CLOCK
1V/div
V+ = 3.3V
1µs/div
40ns/div
V+ = 3.3V
_______________________________________________________________________________________
3
3-Pin Silicon Oscillator
MAX7375
Typical Operating Characteristics (continued)
(V+ = 5V, T
A
= +25°C, C
L
= 10pF, 8MHz output, unless otherwise noted.)
CLOCK OUTPUT WAVEFORM
WITH C
L
= 50pF
MAX7375 toc10
CLOCK OUTPUT WAVEFORM
WITH C
L
= 100pF
MAX7375 toc11
CLOCK
1V/div
CLOCK
1V/div
V+ = 3.3V
40ns/div
40ns/div
V+ = 3.3V
Pin Description
PIN
SC70
1
2
3
SOT23
2
1
3
NAME
V+
CLOCK
GND
Positive Supply Voltage
Clock output. Output is push-pull.
Ground
FUNCTION
Detailed Description
The MAX7375 is a replacement for ceramic resonators,
crystals, and crystal oscillator modules as the clock
source for microcontrollers and UARTs in 3V, 3.3V, and
5V applications. The MAX7375 is an integrated oscilla-
tor, supplied at specific frequencies just like crystals
and resonators. A variety of popular standard frequen-
cies are available. No external components are
required for setting or adjusting the frequency.
positive supply connected 500Ω load to within 300mV
of either supply rail. The clock output remains stable
over the full operating voltage range and does not gen-
erate short output cycles during either power on or
power off. A typical startup characteristic is shown in
the
Typical Operating Characteristics
section.
Output Jitter
The MAX7375’s jitter performance is given in the
Electrical Characteristics
table as a peak-to-peak value
obtained by observing the output of the MAX7375 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 jitter performance of all clock sources degrades in
the presence of mechanical and electrical interference.
The MAX7375 is relatively immune to vibration, shock,
and EMI influences and thus provides a considerably
more robust clock source than crystal- or ceramic-res-
onator-based oscillator circuits.
Supply Voltages
The MAX7375 has been designed for use in systems
with nominal supply voltages of 3V, 3.3V, or 5V and is
specified for operation with supply voltages in the 2.7V
to 5.5V range. Operation outside this range is not guar-
anteed. See the
Absolute Maximum Ratings
table for
limit values of power-supply and pin voltages.
Oscillator
The clock output is a push-pull configuration and is
capable of driving a ground-connected 1kΩ load or a
4
_______________________________________________________________________________________
3-Pin Silicon Oscillator
Applications Information
Interfacing to a Microcontroller Clock
Input
The MAX7375 clock output is a push-pull, CMOS, logic
output, which directly drives any microprocessor (µP)
or microcontroller (µC) clock input. There are no imped-
ance-matching issues when using the MAX7375.
Operate the MAX7375 and microcontroller (or other
clock input device) from the same supply voltage level.
Refer to the microcontroller data sheet for clock input
compatibility with external clock signals.
The MAX7375 requires no biasing components or load
capacitance. When using the MAX7375 to retrofit a
crystal oscillator, remove all biasing components from
the oscillator input.
Extended Temperature Operation
The MAX7375 was tested to +135°C during product
characterization and shown to function normally at this
temperature (see
Typical Operating Characteristics).
However production test and qualification is only per-
formed from -40°C to +125°C at this time. Contact the
factory if operation outside this range is required.
MAX7375
Power-Supply Considerations
The MAX7375 operates with power-supply voltages in
the 2.7V to 5.5V range. Good power-supply decoupling
is needed to maintain the power-supply rejection per-
formance of the MAX7375. Use a 0.1µF surface-mount
ceramic capacitor connected between V+ and GND
and mounted as close to the device as possible. If pos-
sible, mount the MAX7375 close to the microcontroller’s
decoupling capacitor so that additional decoupling is
not required.
A larger value of bypass capacitor is recommended if
the MAX7375 is to operate with a large capacitive load.
Use a bypass capacitor value of at least 1000 times
that of the output load capacitance.
Startup Performance
The MAX7375 oscillator output stabilizes within a few
cycles of operation after V+ rises to a sufficient voltage
to start the oscillator, typically 1.65V at +25°C. Use a
reset or similar voltage-detection circuit to disable
devices connected to the MAX7375 until 5µs after the
voltage on V+ has risen above 2.7V.
Selector Guide
PART
MAX7375AXR105
MAX7375AXR185
MAX7375AXR365
MAX7375AXR375
MAX7375AXR405
MAX7375AXR425
MAX7375AXR805
MAX7375AUR105
MAX7375AUR185
MAX7375AUR365
MAX7375AUR375
MAX7375AUR405
MAX7375AUR425
MAX7375AUR805
FREQUENCY (MHz)
1.00
1.84
3.58
3.69
4.00
4.19
8.00
1.00
1.84
3.58
3.69
4.00
4.19
8.00
TOP MARK
AOV
AOU
AOT
AOS
AOR
AOQ
AOP
FZPZ
FZPT
FZPU
FZPV
FZPY
FZPW
FZPX
CLOCK 2
V+
1
Pin Configuration
TOP VIEW
CLOCK
1
MAX7375AXR
3
GND
V+ 2
MAX7375AUR
3
GND
SC70
SOT23
Chip Information
TRANSISTOR COUNT: 432
PROCESS: BiCMOS
_______________________________________________________________________________________
5
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