MAX7377AXMG [MAXIM]
Analog Circuit, 1 Func, BICMOS, PDSO5, MO-178AA, SOT-23, 5 PIN;
| 型号： | MAX7377AXMG |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Analog Circuit, 1 Func, BICMOS, PDSO5, MO-178AA, SOT-23, 5 PIN 信息通信管理 光电二极管 |
| 文件： | 总8页 (文件大小：992K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
General Description
Features
● 2.7V to 5.5V Operation
The MAX7377 dual-speed silicon oscillator with reset is
a replacement for ceramic resonators, crystals, crystal
oscillator modules, and discrete reset circuits. The device
provides the primary and secondary clock source for
microcontrollers in 3V, 3.3V, and 5V applications. The
MAX7377 features a factory-programmed high-speed
oscillator, a 32.768kHz oscillator, and a clock selec-
tor input. 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 inter-
nally to provide glitch-free clock switching.
● Accurate High-Speed 600kHz to 10MHz Oscillator
● Accurate Low-Speed 32kHz Oscillator
● Glitch-Free Switch Between High Speed and Low
Speed at Any Time
● ±10mA Clock-Output Drive Capability
● 2% Initial Accuracy
● ±50ppm/°C Temperature Coefficient
● 50% Duty Cycle
Unlike typical crystal and ceramic resonator oscillator
circuits, the MAX7377 is resistant to vibration and EMI.
The high-output-drive current and absence of highimped-
ance nodes make the oscillator less susceptible to dirty
or humid operating conditions. With a wide operating
temperature range as standard, the MAX7377 is a good
choice for demanding home appliance and industrial
environments.
● 5ns Output Rise and Fall Time
● Low Jitter: 160ps
at 8MHz (No PLL)
(P-P)
● 3mA Fast-Mode Operating Current (8MHz)
● 13μA Slow-Mode Operating Current (32kHz)
● -40°C to +125°C Temperature Range
The MAX7377 is available in factory-programmed fre-
quencies from 32.768kHz to 10MHz. See Table 1 for
standard frequencies and contact the factory for custom
frequencies.
Ordering Information
PIN-
PKG
CODE
PART
TEMP RANGE
PACKAGE
-40°C to +125°C 5 SOT23-5
The MAX7377 is available in a 5-pin SOT23 package.
Refer to the MAX7383 data sheet for frequencies ≥10MHz.
The MAX7377 standard operating temperature range is
-40°C to +125°C. See the Applications Information sec-
tion for the extended operating temperature range.
MAX7377AX_ _-T
U5-2
The first two letters are AX. See Table 1 at the end of the data
sheet for the two-letter code.
Applications
Pin Configuration
●
●
●
●
White Goods
●
●
Portable Equipment
Microcontroller Systems
Consumer Products
Appliances and Controls
Handheld Products
TOP VIEW
CLOCK
GND
1
2
3
5
4
E.C.
MAX7377
SPEED
V
CC
SOT23
Typical Application Circuit appears at end of data sheet.
19-3474; Rev 3; 4/14
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Absolute Maximum Ratings
V
to GND .............................................................-0.3V to +6V
Operating Temperature Range...........................-40°C to +135°C
Junction Temperature.......................................................+150°C
CC
All Other Pins to GND ................................-0.3V to (V
+ 0.3V)
CC
CLOCK Current ................................................................±10mA
Storage Temperature Range..............................-60°C to +150°C
Continuous Power Dissipation (T = +70°C)
Lead Temperature (soldering, 10s)....
.
.............................+300°C
A
5-Pin SOT23
(derate 7.1mW/°C above +70°C) ...................571mW (U5 - 2)
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 = -40°C to +125°C, unless otherwise noted. Typical values are at V
= 5V and T = +25°C.) (Note 1)
CC
A
CC A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
5.5
5
UNITS
V
Operating Supply Voltage
V
2.7
CC
f
f
= 8MHz, no load
3
mA
µA
CLOCK
Operating Supply Current
I
CC
= 32.768kHz, no load
13
25
CLOCK
Operating Supply Voltage Ramp
LOGIC INPUT (SPEED)
Input High Voltage
V
(Note 4)
10
1000
µs
RAMP
V
0.7 x V
V
V
IH
CC
Input Low Voltage
V
0.3 x V
CC
IL
Input Current
I
2
µA
IN
CLOCK OUTPUT
V
V
V
V
V
V
= 4.5V, I
= 2.7V, I
= 4.5V, I
= 2.7V, I
= 9mA
V
V
- 0.4
- 0.4
CC
CC
CC
CC
CC
CC
SOURCE
CC
Output High Voltage
Output Low Voltage
V
V
V
OH
= 2.5mA
SOURCE
CC
= 20mA
0.4
0.4
+2
SINK
SINK
V
OL
= 10mA
= 5V, T = +25°C (Note 2)
-2
-4
Initial Fast CLOCK Frequency
Accuracy
A
f
%
FCLOCK
= 2.7V to 5.5V, T = +25°C
+4
A
Fast CLOCK Frequency
Temperature Sensitivity
(Note 3)
±50
±325
ppm/oC
kHz
V
V
= 5V, T = +25°C (Note 2)
32.440 32.768 33.096
Initial Slow CLOCK Frequency
Accuracy
CC
A
f
SCLOCK
= 2.7V to 5.5V, T = +25°C
31.785
33.751
±325
57
CC
A
Slow CLOCK Frequency
Temperature Sensitivity
(Note 3)
±50
50
ppm/oC
%
CLOCK Output Duty Cycle
43
Observation of 8MHz output for
20s using a 500MHz oscilloscope
CLOCK Output Jitter
160
ps
P-P
CLOCK Output Rise Time
CLOCK Output Fall Time
Startup Delay
t
10% to 90%
90% to 10%
5
5
ns
R
t
ns
µs
V
F
V
rising from 0 to 5V in 1µs
rising
100
2.57
CC
CC
CLOCK Output Enable
V
2.49
2.70
Output Undervoltage Lockout
Hysteresis
V
45
mV
THYS
Note 1: All parameters are tested at T = +25°C. Specifications over temperature are guaranteed by design.
A
Note 2: The frequency is determined by part number selection. See Table 1.
Note 3: Guaranteed by design. Not production tested.
Note 4: Guaranteed by design. Part will function outside tested range.
Maxim Integrated
│ 2
www.maximintegrated.com
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Typical Operating Characteristics
(V
= 5V, T = +25°C, unless otherwise noted.)
A
CC
DUTY CYCLE vs. TEMPERATURE
DUTY CYCLE vs. TEMPERATURE
DUTY CYCLE vs. SUPPLY VOLTAGE
55
54
55
54
53
52
51
50
49
48
47
46
45
55
54
53
52
51
50
49
48
47
46
45
CLOCK = 4MHz
CLOCK = 32kHz
CLOCK = 32kHz
53
52
51
50
49
48
47
46
45
-55 -30 -5
20 45 70 95 120
-55 -30 -5
20 45 70 95 120
4.3
4.6
4.9
5.2
5.5
TEMPERATURE (∞C)
TEMPERATURE (∞C)
SUPPLY VOLTAGE (V)
DUTY CYCLE vs. SUPPLY VOLTAGE
SUPPLY CURRENT vs. TEMPERATURE
SUPPLY CURRENT vs. TEMPERATURE
55
54
53
52
51
50
49
48
47
46
45
14.0
13.5
13.0
12.5
12.0
11.5
11.0
10.5
10.0
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
CLOCK = 4MHz
CLOCK = 4MHz
CLOCK = 32kHz
4.3
4.6
4.9
5.2
5.5
-55 -30 -5
20 45 70 95 120
-55 -30 -5
20 45 70 95 120
SUPPLY VOLTAGE (V)
TEMPERATURE (∞C)
TEMPERATURE (∞C)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
SUPPLY CURRENT vs. SUPPLY VOLTAGE
FREQUENCY vs. SUPPLY VOLTAGE
30
25
20
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
35.0
34.5
34.0
33.5
33.0
32.5
32.0
31.5
31.0
30.5
30.0
CLOCK = 4MHz
CLOCK = 32kHz
CLOCK = 32kHz
15
10
5
0
4.3
4.6
4.9
5.2
5.5
4.3
4.6
4.9
5.2
5.5
4.3
4.6
4.9
5.2
5.5
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
Maxim Integrated
│
3
www.maximintegrated.com
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Typical Operating Characteristics (continued)
(V
= 5V, T = +25°C, unless otherwise noted.)
A
CC
FREQUENCY vs. SUPPLY VOLTAGE
FREQUENCY vs. TEMPERATURE
FREQUENCY vs. TEMPERATURE
4.10
4.08
33.0
32.9
32.8
32.7
32.6
32.5
32.4
32.3
32.2
32.1
32.0
4.10
4.08
4.06
4.04
4.02
4.00
3.98
3.96
3.94
3.92
3.90
CLOCK = 4MHz
CLOCK = 32kHz
CLOCK = 4MHz
4.06
4.04
4.02
4.00
3.98
3.96
3.94
3.92
3.90
4.3
4.6
4.9
5.2
5.5
-55 -30 -5
20 45 70 95 120
-55 -30 -5
20 45 70 95 120
SUPPLY VOLTAGE (V)
TEMPERATURE (∞C)
TEMPERATURE (∞C)
CLOCK OUTPUT WAVEFORM (C = 10pF)
L
CLOCK OUTPUT WAVEFORM (C = 50pF)
L
CLOCK OUTPUT WAVEFORM (C = 100pF)
L
MAX7377 toc13
MAX7377 toc14
MAX7377 toc15
CLOCK
CLOCK
CLOCK
f = 4MHz, C = 50pF
L
f = 4MHz, C = 100pF
L
f = 4MHz, C = 10pF
L
40ns/div
40ns/div
40ns/div
HIGH-SPEED TO LOW-SPEED
TRANSITION
HIGH-SPEED TO LOW-SPEED
TRANSITION (EXPANDED SCALE)
MAX7377 toc16
MAX7377 toc17
20µs/div
400ns/div
Maxim Integrated
│ 4
www.maximintegrated.com
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Typical Operating Characteristics (continued)
(V
= 5V, T = +25°C, unless otherwise noted.)
A
CC
LOW-SPEED TO HIGH-SPEED
LOW-SPEED TO HIGH-SPEED
TRANSISTION (EXPANDED SCALE)
TRANSITION
MAX7377 toc18
MAX7377 toc19
CLOCK
SPEED
20µs/div
400ns/div
Pin Description
PIN
1
NAME
CLOCK
GND
FUNCTION
Push-Pull Clock Output
Ground
2
Clock-Speed Select Input. Drive SPEED low to select the 32kHz fixed frequency. Drive SPEED high to
select factory-trimmed frequency.
3
SPEED
4
5
V
Positive Supply Voltage. Bypass V
to GND with a 0.1µF capacitor.
CC
CC
E.C.
Externally Connected. Must be externally connected to V
.
CC
Oscillator
Detailed Description
The clock output is a push-pull configuration and is
capable of driving a ground-connected 500Ω or a positive-
supply-connected 250Ω load to within 400mV of either
supply rail. The clock output remains stable over the full
operating voltage range and does not generate short out-
put cycles when switching between high- and low-speed
modes. A typical startup characteristic is shown in the
Typical Operating Characteristics.
The MAX7377 is a dual-speed clock generator for micro-
controllers (μCs) and UARTs in 3V, 3.3V, and 5V applica-
tions. (Figure 1). The MAX7377 is a replacement for two
crystal oscillator modules, crystals, or ceramic resonators.
The high-speed clock frequency is factory trimmed to
specific values. A variety of popular standard frequencies
are available. The low-speed clock frequency is fixed
at 32.768kHz (Table 1). No external components are
required for setting or adjusting the frequency.
Clock-Speed Select Input
Supply Voltage
The MAX7377 uses a logic input pin, SPEED, to set clock
speed. Take this pin low to select slow clock speed (nomi-
nally 32.768kHz) or high to select full clock speed. The
The MAX7377 has been designed for use in systems with
nominal supply voltages of 3V, 3.3V, or 5V and is speci-
fied for operation with supply voltages in the 2.7V to 5.5V
range. See the Absolute Maximum Ratings section for
limit values of power-supply and pin voltages.
SPEED input can be strapped to V
or to GND to select
CC
fast or slow clock speed, or connected to a logic output
(such as a processor port) used to change clock speed
on the fly. If the SPEED input is connected to a processor
Maxim Integrated
│ 5
www.maximintegrated.com
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Output Jitter
V
CC
The MAX7377’s jitter performance is given in the Electrical
Characteristics table as a peak-to-peak value obtained
by observing the output of the MAX7377 for 20s with a
500MHz oscilloscope. Jitter values are approximately
proportional to the period of the output frequency of the
device. Thus, a 4MHz part has approximately twice the jit-
ter value of an 8MHz part. The jitter performance of clock
sources degrades in the presence of mechanical and
electrical interference. The MAX7377 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.
MAX7377
600kHz TO 10MHz
(HF OSCILLATOR)
POR
SPEED
MUX
CLOCK
LOGIC
Initial Power-Up and Operation
An internal power-up reset disables the oscillator until
V
has risen above 2.57V. The clock then starts up
CC
32kHz
(LF OSCILLATOR)
within 30μs (typ) at the frequency determined by the
SPEED pin.
Extended Temperature Operation
The MAX7377 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 per-
formed from -40°C to +125°C at this time. Contact the
factory if operation outside this range is required.
Figure 1. Functional Diagram
port that powers up in the input condition, connect a pullup
or pulldown resistor to the SPEED input to set the clock
to the preferred speed on power-up. The leakage current
through the resistor into the SPEED input is very low, so a
resistor value as high as 500kΩ may be used.
Power-Supply Considerations
The MAX7377 operates with a 2.7V and 5.5V powersup-
ply voltage. Good power-supply decoupling is needed to
maintain the power-supply rejection performance of the
Applications Information
MAX7377. Bypass V
to GND with a 0.1μF surface-
CC
Interfacing to a Microcontroller
Clock Input
mount ceramic capacitor. Mount the bypass capacitor
as close to the device as possible. If possible, mount
the MAX7377 close to the microcontroller’s decoupling
capacitor so that additional decoupling is not required.
A larger value bypass capacitor is recommended if the
MAX7377 is to operate with a large capacitive load. Use
a bypass capacitor value of at least 1000 times that of the
output load capacitance.
The MAX7377 clock output is a push-pull, CMOS, logic
output that directly drives any microprocessor (μP) or μC
clock input. There are no impedance-matching issues
when using the MAX7377. The MAX7377 is not sensi-
tive to its position on the board and does not need to be
placed right next to the μP. Refer to the microcontroller
data sheet for clock-input compatibility with external clock
signals. The MAX7377 requires no biasing components or
load capacitance. When using the MAX7377 to retrofit a
crystal oscillator, remove all biasing components from the
oscillator input.
Maxim Integrated
│ 6
www.maximintegrated.com
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Table 1. Standard Frequencies
Typical Application Circuit
SUFFIX
MG
OK
STANDARD FREQUENCY (MHz)
SUPPLY VOLTAGE
1
1.8432
3.39545
3.6864
4
QT
QW
RD
OSC1
V
CC
CLOCK
RH
4.1943
8
OSC2
E.C.
TP
µC
MAX7377
Note: For all other reset threshold options, contact factory.
I/O PORT
SPEED
Table 2. Standard Part Numbers
PART
MAX7377AXMG
PIN-PACKAGE
5 SOT23
5 SOT23
5 SOT23
5 SOT23
5 SOT23
5 SOT23
5 SOT23
FREQUENCY (Hz)
1M
TOP MARK
AENE
MAX7377AXOK
MAX7377AXQT
MAX7377AXQW
MAX7377AXRD
MAX7377AXRH
MAX7377AXTP
1.8432M
3.39545M
3.6864M
4M
AEND
AEMY
AEMZ
AFBJ
4.1943M
8M
AENB
AENC
Chip Information
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns (foot-
prints), go to www.maximintegrated.com/packages. Note that
a “+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but the
drawing pertains to the package regardless of RoHS status.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
5 SOT23
U5-2
21-0157
90-0174
Maxim Integrated
│ 7
www.maximintegrated.com
MAX7377
Silicon Oscillator with Low-Power
Frequency Switching
Revision History
REVISION REVISION
PAGES
CHANGED
DESCRIPTION
No /V OPNs; removed Automotive reference from Applications section
NUMBER
DATE
3
4/14
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
©
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
2014 Maxim Integrated Products, Inc.
│ 8
相关型号：
©2020 ICPDF网 联系我们和版权申明