19-3493; Rev 1; 2/05
Silicon Oscillator with Low-Power Frequency
Switching and Reset Output
General Description
The MAX7384 dual-speed silicon oscillator replaces
ceramic resonators, crystals, and crystal-oscillator
modules as the primary and secondary clock source for
microcontrollers in 3V, 3.3V, and 5V applications. The
MAX7384 features a factory-programmed high-speed
oscillator, a 32.768kHz oscillator, a clock-selector input,
and a µP power-on-reset (POR) supervisor. The clock
output can be switched at any time between the high-
speed clock and the 32.768kHz clock for low-power
operation. Switchover is synchronized internally to pro-
vide glitch-free clock switching.
Unlike typical crystal and ceramic-resonator oscillator
circuits, the MAX7384 is resistant to vibration and EMI.
The high-output-drive current and absence of high-
impedance nodes makes the oscillator less susceptible
to dirty or humid operating conditions. With a wide oper-
ating temperature range as standard, the MAX7384 is a
good choice for demanding home appliance, industrial,
and automotive environments.
The MAX7384 is available with factory-programmed fre-
quencies ranging from 10MHz to 32MHz. See Table 1
for standard frequencies and contact the factory for
custom frequencies. Refer to the MAX7378 data sheet
for frequencies less than 10MHz.
The MAX7384 is available in an 8-pin µMAX
®
package.
The MAX7384 standard operating temperature range is
-40°C to +125°C. See the
Applications Information
sec-
tion for extended operating temperature range.
Features
♦
2.7V to 5.5V Operation
♦
High-Speed Oscillator from 10MHz to 32MHz
Low-Speed 32kHz Oscillator
Glitch-Free Clock-Speed Switching
♦
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
♦
13µA, 32kHz Operating Current
♦
-40°C to +125°C Temperature Range
MAX7384
Ordering Information
PART*
MAX7384A_ _ _
MAX7384B_ _ _
MAX7384C_ _ _
TEMP RANGE
PIN-
PACKAGE
RESET
OUTPUT
Active high
push-pull
Active low
push-pull
Open drain
-40°C to +125°C 8 µMAX
-40°C to +125°C 8 µMAX
-40°C to +125°C 8 µMAX
Applications
White Goods
Automotive
Consumer Products
Appliances and Controls
Handheld Products
Portable Equipment
Microcontroller Systems
*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.
Typical Application Circuit
V
CC
2.7V TO 5.5V
0.1µF
0.1µF
V
CC
V
L
CLOCK
OSC1
OSC2
MAX7384
E.C.
RST/RST
SPEED
GND
RST
I/O PORT
µC
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Pin Configuration appears at end of data sheet.
________________________________________________________________
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.
Silicon Oscillator with Low-Power Frequency
Switching and Reset Output
MAX7384
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ...........................................................-0.3V to +6.0V
All Other Pins to GND.................................-0.3V to (V
CC
+ 0.3V)
CLOCK, RST Current .......................................................±50mA
Input Current (SPEED)......................................................±50mA
Continuous Power Dissipation (T
A
= +70°C)
8-Pin µMAX (derate 4.5mW/°C above +70°C) ...362mW (U8-1)
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,
V
CC
= 2.7V to 5.5V, V
L
= V
CC
, T
A
= -40°C to +125°C. Typical values are at V
CC
= 5.0V, T
A
= +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
Operating Supply Voltage
SYMBOL
V
CC
f
CLOCK
= 16MHz, T
A
= -40°C to +125°C, no
load
f
CLOCK
= 14.7456MHz, T
A
= -40°C to
+125°C, no load
f
CLOCK
= 12MHz, T
A
= -40°C to +125°C, no
load
Operating Supply Current
I
CC
f
CLOCK
= 11.0592MHz, T
A
= -40°C to
+125°C, no load
f
CLOCK
= 10MHz, T
A
= -40°C to +125°C, no
load
f
CLOCK
= 32.768kHz, T
A
= -40°C to
+125°C, no load
LOGIC INPUTS (SPEED)
Input High Voltage
Input Low Voltage
Input Current
CLOCK OUTPUT
Output High Voltage
Output Low Voltage
V
OH
V
OL
V
L
= 4.5V, I
SOURCE
= 7.0mA
V
L
= 2.7V, I
SOURCE
= 2.0mA
V
L
= 4.5V, I
SINK
= 20mA
V
L
= 2.7V, I
SINK
= 10mA
V
CC
= 5V, T
A
= +25°C, deviation from
selected frequency
f
CLOCK
V
CC
= 2.7V to 5.5V, T
A
= +25°C,
deviation from selected frequency
T
A
= -40°C to +125°C
-2.5
-5
±50
V
L
- 0.4
0.4
+2.5
%
+3.5
±350
ppm/°C
V
V
V
IH
V
IL
I
IN
V
CC
= SPEED = 5.5V
0.7 x V
CC
0.3 x V
CC
2
µA
V
13
CONDITIONS
MIN
2.7
TYP
MAX
5.5
8.7
8.0
6.5
6.0
5.4
25
µA
mA
UNITS
V
Initial Fast Clock Frequency
Accuracy
Fast Clock Temperature
Coefficient
2
_______________________________________________________________________________________
Silicon Oscillator with Low-Power Frequency
Switching and Reset Output
ELECTRICAL CHARACTERISTICS (continued)
(Typical
Operating Circuit,
V
CC
= 2.7V to 5.5V, V
L
= V
CC
, T
A
= -40°C to +125°C. Typical values are at V
CC
= 5.0V, T
A
= +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
Slow Clock Frequency
Slow Clock Temperature
Coefficient
Duty Cycle
Output Jitter
Output Rise Time
Output Fall Time
Power-On-Reset Threshold
t
R
t
F
V
TH
SYMBOL
f
CLOCK
CONDITIONS
V
CC
= 5V, T
A
= +25°C
V
CC
= 2.7V to 5.5V, T
A
= +25°C
T
A
= -40°C to +125°C
(Note 2)
Observation of 16MHz for 20s using a
12GHz oscilloscope
10% to 90%
90% to 10%
V
CC
rising, deviation
from nominal threshold
T
A
= +25°C
T
A
= -40°C to
+125°C
-2
-5
1
122
V
CC
-
0.4
V
V
L
= 2.7V, I
SOURCE
= 2.0mA
Output Low Voltage
V
OL
V
L
= 4.5V, I
SINK
= 20mA
V
L
= 2.7V, I
SOURCE
= 10mA
V
CC
-
0.4
0.4
0.4
V
40
MIN
32.268
31.768
TYP
32.768
32.768
±50
50
80
5
5
+2
+5
%
MAX
33.268
33.768
±325
60
UNITS
kHz
ppm/°C
%
ps
P-P
ns
ns
MAX7384
Power-On-Reset Hysteresis
Power-On-Reset Delay
RESET OUTPUT
Output High Voltage
(Note 3)
V
HYST
PORdly
Difference between rising and falling
thresholds
V
CC
rising from 0 to 5V in 1µs at +25°C
%
µs
V
L
= 4.5V, I
SOURCE
= 7.0mA
V
OH
Note 1:
All parameters tested at T
A
= +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
Silicon Oscillator with Low-Power Frequency
Switching and Reset Output
MAX7384
Typical Operating Characteristics
(V
CC
= V
L
= 5V, T
A
= +25°C, frequency = 10MHz, unless otherwise noted.)
DUTY CYCLE vs. SUPPLY VOLTAGE
MAX7384 toc02
MAX7384 toc01
DUTY CYCLE vs. TEMPERATURE
50.5
51
SUPPLY CURRENT vs. TEMPERATURE
MAX7384 toc03
3.25
3.20
SUPPLY CURRENT (mA)
3.15
3.10
FREQUENCY = 10MHz
3.05
3.00
2.95
2.90
FREQUENCY = 11.0592MHz
50
DUTY CYCLE (%)
49
48
47
46
45
50.0
DUTY CYCLE (%)
49.5
FREQUENCY = 10MHz
49.0
48.5
48.0
-55
-17
21
59
97
135
TEMPERATURE (°C)
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
-55
-17
21
59
97
135
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX7384 toc04
FREQUENCY DEVIATION
vs. SUPPLY VOLTAGE
FREQUENCY = 11.0592MHz
1.5
FREQUENCY DEVIATION (%)
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
MAX7384 toc05
FREQUENCY DEVIATION
vs. TEMPERATURE
FREQUENCY = 10MHz
3
FREQUENCY DEVIATION (%)
2
1
0
-1
-2
-3
-4
MAX7384 toc06
4.0
FREQUENCY = 11.0592MHz
3.5
SUPPLY CURRENT (mA)
2.0
4
3.0
2.5
2.0
1.5
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
SUPPLY VOLTAGE (V)
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
-55
-17
21
59
97
135
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
SETTLING TIME FROM START
MAX7384 toc07
CLOCK OUTPUT WAVEFORM
(C
L
= 10pF)
MAX7384 toc08
CLOCK OUTPUT WAVEFORM
(C
L
= 50pF)
MAX7384 toc09
CH1 FREQ
9.992MHz
LOW RESOLUTION
10µs/div
CHANNEL 1 = CLOCK, CHANNEL 2 = V
CC
20ns/div
20ns/div
4
_______________________________________________________________________________________
Silicon Oscillator with Low-Power Frequency
Switching and Reset Output
MAX7384
Typical Operating Characteristics (continued)
(V
CC
= V
L
= 5V, T
A
= +25°C, frequency = 10MHz, unless otherwise noted.)
CLOCK OUTPUT WAVEFORM
(C
L
= 100pF)
MAXIMUM TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
MAXIMUM TRANSIENT DURATION (s)
MAX7384 toc11
HIGH-SPEED TO LOW-SPEED
TRANSITION
MAX7384 toc12
MAX7384 toc10
1
0.1
0.01
1m
10m
100m
1µ
0.04
V
RESET
= 4.32V
20ns/div
0.09
0.14
0.19
0.24
10µs/div
CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED
RESET THRESHOLD OVERDRIVE (V)
HIGH-SPEED TO LOW-SPEED
TRANSITION
MAX7384 toc13
LOW-SPEED TO HIGH-SPEED
TRANSITION
MAX7384 toc14
LOW-SPEED TO HIGH-SPEED
TRANSITION
MAX7384 toc15
40ns/div
CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED
10µs/div
CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED
100ns/div
CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED
SUPPLY CURRENT vs. FREQUENCY
MAX7384 toc16
5
SUPPLY CURRENT (mA)
4
3
2
1
10
11
12
13
14
15
16
FREQUENCY (MHz)
_______________________________________________________________________________________
5
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