MAX6666AUA+T [MAXIM]
Analog Voltage Output Sensor, 0.4V Min, 5.1V Max, 2.50Cel, BICMOS, Square, 8 Pin, Surface Mount, MICRO MAX PACKAGE-8;型号: | MAX6666AUA+T |
厂家: | MAXIM INTEGRATED PRODUCTS |
描述: | Analog Voltage Output Sensor, 0.4V Min, 5.1V Max, 2.50Cel, BICMOS, Square, 8 Pin, Surface Mount, MICRO MAX PACKAGE-8 信息通信管理 输出元件 传感器 换能器 |
文件: | 总7页 (文件大小:563K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
19-2138; Rev 2; 12/05
High-Accuracy PWM Output Temperature
Sensors
General Description
Features
The MAX6666/MAX6667 are high-accuracy, low-cost,
low-power temperature sensors with a single-wire
output. The MAX6666/MAX6667 convert the ambient
temperature into a ratiometric PWM output with temper-
ature information contained in the duty cycle of the out-
put square wave. The MAX6666 has a push-pull output
and the MAX6667 has an open-drain output.
♦ Simple Single-Wire PWM Output
♦ ±±1.0° ꢀAAurꢁAc ꢁt ꢂ+20°
♦ High ꢀAAurꢁAc
±±0° ꢁt ꢃ = ꢂ3.0°
ꢀ
±+120° ꢁt ꢃ = ꢂ±.0° to ꢂ2.0°
ꢀ
♦ Operꢁte Up to ꢂ±+20°
The MAX6666/MAX6667 operate at supply voltages
from +3V to +5.5V. The typical unloaded supply current
at 5.0V is 200µA. Both devices feature a single-wire
output that minimizes the number of pins necessary to
interface with a microprocessor (µP). The output is a
square wave with a nominal frequency of 35Hz ( 20ꢀ)
at +25°C. The output format is decoded as follows:
♦ Low +..µꢀ ꢃcpiAꢁl °urrent °onsumption
♦ Smꢁll SOꢃ-+3 pꢁAkꢁge
Temperature (°C) = 235 - (400 x t ) / t
1
2
Where t is fixed with a typical value of 10ms and t is
1
2
modulated by the temperature (Figure 1). The MAX6666/
MAX6667 operate from -40°C to +125°C and are available
in space-saving SOT23 packages.
Applications
Ordering Information
Process Control
PꢀRꢃ
ꢃEMP RꢀNGE
PIN-Pꢀ°KꢀGE
Industrial
MꢀX6666AUT-T
MꢀX6667AUT-T
-40°C to +125°C 6 SOT23-6
-40°C to +125°C 6 SOT23-6
HVAC and Environmental Control
Automotive
µP and µC Temperature Monitoring
Typical Operating Circuit
Pin Configuration
TOP VIEW
+3.3V
t
1
V
CC
6
5
4
D
1
2
3
IC
IC
IC
OUT
t
2
MAX6666
MAX6667
µC
MAX6666
MAX6667
V
CC
INPUT TO
TIMER/COUNTER
DOUT
GND
GND
SOꢃ+3
________________________________________________________________ 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.
High-Accuracy PWM Output Temperature
Sensors
ꢀBSOLUꢃE MꢀXIMUM RꢀꢃINGS
(Voltages Referenced to GND)
Continuous Power Dissipation (T = +70°C)
A
V
D
........................................................................-0.3V to +6.0V
6-Pin SOT23 (derate 8.7mW/°C above +70°C).........695.7mW
Operating Temperature Range .........................-40°C to +150°C
Storage Temperature Range.............................-65°C to +150°C
Junction Temperature......................................................+150°C
Lead Temperature (soldering,10s).....................................+150°
CC
OUT
MAX6666................................................-0.3V to (V
+ 0.3V)
CC
MAX6667..........................................................-0.3V to + 6.0V
Current ......................................................-1mA to +50mA
D
OUT
Continuous Current into Any Other Terminal.................... 20mA
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.
ELE°ꢃRI°ꢀL °HꢀRꢀ°ꢃERISꢃI°S
(V
= +3.0V to +5.5V, T = -40°C to +125°C, unless otherwise noted. Typical values are at V
= +3.3V, T = +25°C.)
CC A
CC
A
PꢀRꢀMEꢃER
SYMBOL
°ONDIꢃIONS
MIN
ꢃYP
MꢀX
5.5
UNIꢃS
V
Supply Voltage Range
Supply Current
V
3.0
CC
CC
I
V
V
= +3.0V to +5.5V
200
500
+1
µA
CC
CC
T
= +30°C
-1
A
T = +10°C to +50°C
A
-2.5
-3.8
-4.8
-6
+2.5
+3.8
+4.8
+6
Temperature Error
= +3.3V
T = 0°C to +100°C
A
°C
T = -25°C to +125°C
A
T = -40°C, V = +3.3V
A
CC
Nominal t Pulse Width
1
10
ms
V
MAX6666 Output High Voltage
MAX6666 Output Low Voltage
MAX6666 Fall Time
I
I
= 800µA
V
CC
- 0.4
OH
= 800µA
0.4
V
OL
C = 100pF, R = ∞
80
80
ns
ns
L
L
MAX6666 Rise Time
C = 100pF, R = ∞
L
L
I
= 1.6mA
= 5.0mA
0.4
1.2
SINK
SINK
MAX6667 Output Low Voltage
V
I
MAX6667 Fall Time
C = 100pF, R = 10kΩ
40
15
ns
pF
L
L
MAX6667 Output Capacitance
MAX6667 Output Leakage
Power-Supply Rejection Ratio
C = 0
L
<0.1
0.3
µA
PSRR
V
= +3.0V to +5.5V
1.0
°C/V
CC
+
_______________________________________________________________________________________
High-Accuracy PWM Output Temperature
Sensors
Typical Operating Characteristics
(V
CC
= +3.3V, T = +25°C, unless otherwise noted.)
A
T AND T TIMES
1
2
OUTPUT FREQUENCY vs. TEMPERATURE
OUTPUT FREQUENCY vs. SUPPLY VOLTAGE
vs. TEMPERATURE
50
40
30
20
10
0
45
39
34
TEMP = +125°C
TWO TYPICAL PARTS
40
35
30
25
20
29
24
19
TEMP = +25°C
T
2
T
1
TEMP = -40°C
14
9
-40
-10
20
50
80
110
140
-40 -15
10
35
60
85
110
3.0
3.5
4.0
4.5
5.0
5.5
TEMPERATURE (°C)
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
OUTPUT ACCURACY
vs. TEMPERATURE
SUPPLY CURRENT
vs. TEMPERATURE
SUPPLY CURRENT vs. SUPPLY VOLTAGE
210
200
3
158
156
154
152
150
148
146
144
142
140
190
180
170
2
1
V
= +5.5V
CC
160
150
140
0
V
CC
= +3.3V
-1
-2
-3
130
120
110
100
-40
-10
20
50
80
110
-55 -25
5
35
95 125 155
65
3.0
3.5
4.0
4.5
5.0
5.5
TEMPERATURE (°C)
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
POWER-SUPPLY REJECTION RATIO
vs. TEMPERATURE
POWER-SUPPLY REJECTION
vs. FREQUENCY
1.0
0.5
0
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
-0.5
-1.0
V
AC
= 100mVp-p
0
0.01
0.1
1
10
100
1k
10k
-40
-15
10
35
60
85 110
TEMPERATURE (°C)
FREQUENCY (Hz)
_______________________________________________________________________________________
3
High-Accuracy PWM Output Temperature
Sensors
Typical Operating Characteristics (continued)
(V
CC
= +3.3V, T = +25°C, unless otherwise noted.)
A
MAX6666
OUTPUT RISE AND FALL TIMES
vs. CAPACITIVE LOADS
MAX6666
OUTPUT FALL TIME
MAX6666/7 toc09
1200
1000
800
C
= 100pF
LOAD
R = 100kΩ
L
FALL TIME
RISE TIME
1V/div
600
400
200
0
0
300
600
900
(pF)
1200
1500
40ns/div
C
LOAD
OUTPUT LOW VOLTAGE
vs. TEMPERATURE
OUTPUT HIGH VOLTAGE
VS. TEMPERATURE
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
3.30
3.25
3.20
3.15
3.10
3.05
3.00
V
CC
= +3.3V
I
= 800µA
SOURCE
I
= 5mA
SINK
I
= 1.5mA
SINK
I
= 1mA
SINK
-40 -20
0
20 40 60 80 100 120 140
-40 -20
0
20 40 60 80 100 120 140
TEMPERATURE (°C)
TEMPERATURE (°C)
Pin Description
PIN
1
NꢀME
FUN°ꢃION
D
Digital Output Pin. The pulse width of the output waveform is modulated by the temperature.
OUT
2
V
Supply Voltage
CC
3
GND
IC
Ground
4, 5, 6
Internally Connected. Leave unconnected or connect to GND.
4
_______________________________________________________________________________________
High-Accuracy PWM Output Temperature
Sensors
Detailed Description
t
1
The MAX6666/MAX6667 are high-accuracy, low-cost,
low current (200µA typ) temperature sensors ideal for
interfacing with µCs or µPs. The MAX6666/MAX6667
convert the ambient temperature into a ratiometric
PWM output at a nominal frequency of 35Hz ( 20ꢀ) at
+25°C.
t
2
The time periods, t (high) and t (low) (Figure 1), are
1
2
easily read by the µP’s timer/counter port. To calculate
the temperature, use the expression below:
Figure 1. MAX6666/MAX6667 PWM Output
Temperature (°C) = +235 - (400 x t ) / t
1
2
Power-Supply Bypassing
The µC or µP measures the output of the MAX6666/
MAX6667 by counting t and t and computing the
The MAX6666/MAX6667 operate from a +3V to +5.5V
supply. If a noisy power-supply line is used, bypass
CC
1
2
temperature based on their ratio. The resolution of the
count is a function of the processor clock frequency
and the resolution of the counter. The MAX6666/
MAX6667 have a resolution of approximately 11 bits.
V
to GND with a 0.1µF capacitor.
Power Supply from µP Port Pin
The low quiescent current of the MAX6666/MAX6667
enables it to be powered from a logic line, which meets
the requirements for supply voltage range. This pro-
vides a simple shutdown function to totally eliminate
quiescent current by taking the logic line low. The logic
line must be able to withstand the 0.1µF power-supply
bypass capacitance.
Always use the same clock for t and t counters so
1
2
that the temperature is strictly based on a ratio of the
two times, thus eliminating errors due to different
clocks’ frequencies.
The MAX6666 (Figure 2a) has a push-pull output and
provides Rail-to Rail® output drive. The ability to source
and sink current allows the MAX6666 to drive capaci-
tive loads up to 10nF with less than 1°C error.
Galvanic Isolation
Use an optocoupler to isolate the MAX6666/MAX6667
whenever a high common-mode voltage is present.
Because some optocouplers have turn-off times that
are much longer than their turn-on times, choose an
optocoupler with equal turn-on and turn-off times.
Unequal turn-on/turn-off times produce an error in the
temperature reading.
The MAX6667 (Figure 2b) has an open-drain output.
The output capacitance should be minimized in
MAX6667 applications because the sourcing current is
set by the pullup resistor. If the output capacitance
becomes too large, lengthy rise and fall times distort
the pulse width, resulting in inaccurate measurements.
Applications Information
Thermal Considerations
Self-heating may cause the temperature measurement
accuracy of the MAX6666/MAX6667 to degrade in
some applications. The quiescent dissipation and the
power dissipated by the digital output may cause
errors in obtaining the accurate temperature measure-
ment. The temperature errors depend on the thermal
conductivity of the package (SOT23, 140°C/W), the
mounting technique, and the airflow. Static dissipation
in the MAX6666/MAX6667 is typically 4.5mW operating
at 5V with no load. As a worst-case example, consider
the MAX6667 and its maximum rated load of 5mA and
assume a maximum output voltage of 0.8V adds 4mW
power dissipation. Use Figure 3 to estimate the temper-
ature error.
Accurate temperature monitoring requires a good ther-
mal contact between the MAX6666/MAX6667 and the
object being monitored. A precise temperature mea-
surement depends on the thermal resistance between
the object being monitored and the MAX6666 die. Heat
flows in and out of plastic packages primarily through
the leads. For the best thermal contact, connect all
unused pins to ground. If the sensor is intended to
measure the temperature of a heat-generating compo-
nent on the circuit board, mount the device as close as
possible to that component and share the ground
traces (if they are not too noisy) with the component.
This maximizes the heat transfer from the component to
the sensor.
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
_______________________________________________________________________________________
2
High-Accuracy PWM Output Temperature
Sensors
V
CC
V
CC
+3.3V
2.5V
P
DOUT
DOUT
5.1kΩ
MAX6667
N
N
DOUT
TO LOGIC GATE INPUT
GND
(a)
(b)
Figure 4. Low-Voltage Logic
Figure 2. MAX6666/MAX6667 Output Configuration
MAX6666
TEMPERATURE ERROR vs. LOAD CURRENT
3.5
3.0
µMAX
2.5
SO
2.0
1.5
1.0
SOT23-6
0.5
0
0
2
4
6
8
10
LOAD CURRENT (mA)
Figure 3. MAX6666 Temperature Error Due to Load Current
Low-Voltage Logic
Use the MAX6667 open-drain output to drive low-volt-
age devices. As shown in Figure 4, connect a pullup
resistor from the low-voltage logic supply to the
MAX6667 output. Limit the resistor’s current to about
1mA, thus maintaining an output low logic level of less
than 200mV.
Chip Information
TRANSISTOR COUNT: 6479
PROCESS: BiCMOS
6
_______________________________________________________________________________________
High-Accuracy PWM Output Temperature
Sensors
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 www1mꢁxim-iA1Aom/pꢁAkꢁges.)
PACKAGE OUTLINE, SOT 6L BODY
1
21-0058
G
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 7
© 2005 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.
相关型号:
MAX6666AUA-T
Analog Voltage Output Sensor, 0.4V Min, 5.1V Max, 2.50Cel, BICMOS, Square, 8 Pin, Surface Mount, MICRO MAX PACKAGE-8
MAXIM
MAX6666AUT
ANALOG TEMP SENSOR-VOLTAGE, 2.50Cel, RECTANGULAR, SURFACE MOUNT, MO-178AB, SOT-23, 6 PIN
ROCHESTER
MAX6666AUT
Analog Voltage Output Sensor, 0.4V Min, 5.1V Max, 2.50Cel, Rectangular, Surface Mount, MO-178AB, SOT-23, 6 PIN
MAXIM
MAX6667ASA+
Analog Voltage Output Sensor, 0.4V Min, 5.1V Max, 2.50Cel, Rectangular, Surface Mount, 0.150 INCH, SOIC-8
MAXIM
MAX6667ASA-T
Analog Voltage Output Sensor, 0.4V Min, 5.1V Max, 2.50Cel, BICMOS, Rectangular, 8 Pin, Surface Mount, 0.150 INCH, SOIC-8
MAXIM
©2020 ICPDF网 联系我们和版权申明