1-Wire Technology Simplifies Humidity
And Temperature Measurement:
12/18/00 Electronic Design - Ideas for Design / A
new 1-Wire technology component, the DS2438 Smart
Battery Monitor provides several functions.
Developed by Dallas Semiconductor, this device
offers a unique 64- bit serial number, an internal
temperature sensor, and an A/D that measures both
the. . . |
|
2 Chip Digital Thermometer Delivers
0.4�C Accuracy :
07/08/02 Electronic Design - Ideas
for Design / An LED digital thermometer with
an operating range between 0�C and 150�C, 1�C
resolution, and �0.4�C accuracy is presented in the
figure. This design is based on the PIC16F872... |
4-To-20-mA Loop Powers Temperature
Sensor:
05/07/01 Electronic Design - Ideas
for Design / Using an analog temperature
sensor, an op amp, a transistor, and a low-dropout
linear regulator, this circuit provides a 4-to-20-mA
output over a 3.75- to 28-V compliance range (see
the figure).. . . |
Accelerometer Output gives
Temperature Info:
11/19/98 EDN-Design Ideas
|
ADC's Reference Improves RTD
Measurements:
10/27/94 EDN-Design Ideas
|
AT89C2051 Digital Thermometer & Clock:
|
BASIC Stamp Thermoelectric Cooler: |
Build A Digital Temp Monitor:
04/03/00 Electronic Design - Ideas for Design /
This Idea for Design was originally published Dec.
2, 1993. The AD590
proportional-to-absolute-temperature (PTAT) device
combined with an autoranging digital multimeter (DMM),
such as Fluke's Model 77, can make a stable digital.
. . |
Circuit Linearizes, Converts
Thermistor Data:
12/07/95 EDN-Design Ideas
|
Circuit provides cold junction
compensation:
11/28/2002 EDN - Design Ideas /
The accuracy of any circuit or system that uses a
thermocouple to determine the temperature of a
process is limited by the accuracy of the method
used to perform cold-junction compensation. In a
thermocouple measurement, two wires of dissimilar
metal join together at the "hot," or measurement,
junction.. |
Digital Remote Thermometer:
Remote sensor sends data via mains supply
Temperature range:00.0 to 99.9 �C
|
DS1820 Temperature Sensor Readout
Unit:
|
IC Diodes help Deduce Junction
Temperature:
07/07/94 EDN-Design Ideas |
IC removes nonlinear temperature
effects :
09/25/03 EDN-Design Ideas / A common
technique for removing nonlinear temperature-related
effects from a dc voltage is to incorporate a
temperature sensor that a microprocessor samples via
an A/D converter. The processor determines—by
mathematical calculation or a temperature-indexed
look-up table—the amount of adjustment is necessary
at a given temperature and delivers the resulting
value via a D/A converter.... |
IC Temperature Sensor Provides
Thermocouple ColdJunction Compensation:
National Semiconductor Application Notes,04-Nov-1995
|
Interfacing A Single-Wire
Temperature-Sensor IC To A PC:
07/24/00 Electronic Design - Ideas for Design / Over
the years, vendors have introduced a large
assortment of temperature-measuring semiconductor
devices with varying interfacing techniques. One of
the latest of these, Maxim’s MAX6577, can measure
temperature over a range of −40�C to. . . |
LCD Thermometer: |
LM34 / LM35 Precision Monolithic
Temperature Sensors:
National Semiconductor Application Notes,04-Nov-1995 |
Low Cost Digital Thermometer Uses
SingleChip Microcontroller
: 02/18/02 Electronic Design - Ideas
for Design / In many applications, the ability to
read and display temperature is either desirable or
an absolute requirement. Some of these applications
include temperature probes, thermostats, CPU
monitors, and process-control equipment. The ... |
Low Cost Digital Thermometer Uses
SingleChip Microcontroller
: 02/18/02 Electronic Design - Ideas
for Design / In many applications, the ability to
read and display temperature is either desirable or
an absolute requirement. Some of these applications
include temperature probes, thermostats, CPU
monitors, and process-control equipment. The ... |
Low-Cost Digital Thermometer Uses
Single-Chip Microcontroller:
02/18/02 Electronic Design - Ideas for Design / In
many applications, the ability to read and display
temperature is either desirable or an absolute
requirement. Some of these applications include
temperature probes, thermostats, CPU monitors, and
process-control equipment. The . . . |
Measure humidity and temperature on
one TTL line: 08/30/2001
EDN - Design Ideas / By combining the responses of
an Analog Devices (www.analog.com) AD590 temperature
sensor and a Humirel (www.humirel.com) HS1101
humidity sensor, you can generate a single TTL-level
signal containing information from both sensors
(Figure 1). This design uses a 74HC123 monostable
multivibrator, IC1, to form a free-running
oscillator. . |
Measure temperature in remote
locations: 10/12/00 EDN-Design
Ideas / PDF contains multiple circuits - scroll to
find this circuit |
Micropower Thermometer:
National Semiconductor Application Notes,28-Jun-1996
|
Miniature temperature monitors drive
3-speed fan controller:
02/22/99 Electronic Design - Ideas for Design /
Combining a switch-mode dc-dc controller with two
low-cost temperature monitor ICs produces a
three-speed fan controller (see the figure). This
useful. . . |
Monitor Your PC's CPU Core
Temperature: 09/05/00
Electronic Design - Ideas for Design / This circuit
can be used to determine the core temperature of
your PC’s CPU and display it on a monitor (Fig. 1).
Installing such a circuit can help to ensure that
your system’s cooling is. . . |
Network imitates thermocouples:
11/08/2001 EDN - Design Ideas / Thermocouples find
widespread use for temperature measurement in
systems. During system design or testing, you must
observe the system's response at different
temperatures. However, it's inconvenient to heat a
thermocouple every time you need to check a system's
performance. You can use the simple trick of
touching the thermocouple with a hot soldering iron,
but this method provides only ... . |
Network of RS-485 smart temperature
sensors: 08/23/99
Electronic Design - Ideas for Design / The system
described here implements a smart temperature-sensor
network. In this particular application, each of the
intelligent network nodes is equipped with two
temperature. . . |
Oscillators Convert Temperature to
Time: 03/30/95 EDN-Design
Ideas |
Parallel port provides high
resolution temperature sensing:
10/03/2002 EDN - Design Ideas /
High-resolution temperature sensing at low cost is
possible using only one chip attached to the PC's
parallel port (Figure 1). The Dallas Semiconductor (www.dalsemi.com)
DS1722 digital thermometer allows measurement
resolution as fine as 0.0625�C in digital form and
with linear response. The accuracy specification is
only 2�C, but you can improve this figure by careful
calibration.. |
PC Thermometer: |
Precision Thermometer Linearizes,
Digitally Calibrates Platinum RTDs:
05/29/00 Electronic Design - Ideas for Design /
Among temperature transducers, the platinum
resistance temperature detector (PRTD) is generally
accepted as the “gold standard.” PRTDs are available
with interchangeability accuracies as tight as 0.1�C
over operational ranges extending from. . . |
Precision Thermostat Uses TBH And AC
Feed-Forward Compensation:
03/19/01 Electronic Design - Ideas for Design /
Precision temperature control with relatively
high-power heaters driven directly from unregulated
"120-V" ac lines is an efficient, inexpensive way to
manage large thermal loads. A number of annoying
complications can render this straightforward. . . |
Protect Digital Temperature
Sensor In Noisy Environments
: 06/21/04 Electronic
Design - Design Briefs / Using digital
temperature-sensing methods in a noisy
environment is difficult, if not downright
impossible. Noise is easily coupled into the
temperature-sensing circuit and can result
in a large temperature error. In fact, a
very noisy environment can...
|
|
: 03/04/02 Electronic Design - Ideas
for Design / Before the MAX6629/30/31/32 series of
temperature sensors were available, all
digital-output temperature sensors were I2C
(alternatively called SMBus) sensors that had to be
written to for addressing, before they were read.
Prior SPI... |
: 12/21/95 EDN-Design
Ideas |
Self-Heated Transistor Thermo-stats
Individual Components:
02/09/98 Electronic Design - Ideas for Design /
An unavoidable fact of life is that all parameters
of all electronic components drift with temperature.
Even the best voltage references, op amps, crystal
oscillators, etc., have non-zero temperature
coefficients. These effects can be handled by. . . |
Sense junction temperatures without
calibration: 05/13/98
Electronic Design - Ideas for Design /
Transistors can be used as a low-cost temperature
sensors. Sensing temperature with a silicon junction
often exploits the fact that the forward voltage
drop has a temperature coefficient of −2.2 mV/�C.
The problem with this method is that. . . |
Sensing Method Increases Thermal
Response Time: 1/04/96
EDN-Design Ideas |
Shower Stopper: |
Simple design equations for
thermoelectric coolers:
02/23/98 Electronic Design - Ideas for Design /
Thermoelectric coolers (TECs) are versatile
temperature control devices. They’re best thought of
as solid-state heat pumps in which the direction and
rate of heat flow can be manipulated by controlling
the magnitude and polarity of the TEC drive. . . |
Simplify Isolated Temperature Sensing
With Single-Wire Sensors:
06/26/00 Electronic Design - Ideas for Design /
Galvanic isolation of sensors, such as temperature
sensors, is required since these sensors are often
mounted in "mechanically inconvenient" locations.
"Mechanically inconvenient" often implies an
electrically noisy environment, an environment
where. . . |
Single Supply Circuit Linearizes RTDs:
12/21/95 EDN-Design Ideas |
Single-Gate VHF Temperature
Transmitter Runs On 3.6 V:
12/03/01 Electronic Design - Ideas for Design / This
design idea illustrates what may be the simplest and
smallest temperature transmitter in the VHF 50- to
100-MHz range. As seen in the figure, the design
employs an ON SEMI single-gate IC (NL27WZ14). The. .
. |
Take Back Half: A Novel Integrating
Temperature-Control Algorithm:
12/04/00 Electronic Design - Ideas for Design /
According to Linear Technology’s Jim Williams, “The
unfortunate relationship between servo systems and
oscillators is very apparent in thermal control
systems.” (Linear Applications Handbook, 1990).
High-performance temperature control is. . . |
Take-Back-Half HVAC Thermostat Is
Precise And Energy-Efficient:
07/09/01 Electronic Design - Ideas for Design /
Implementing tight control of environmental
temperature is essential in many critical areas. For
instance, it's necessary when research laboratories
house sensitive instrumentation and for
manufacturing facilities involved in high-precision.
. . |
Temperature Compensated PH Meter: |
Temperature Controlled Based on
AT89CX051: |
Temperature measurement scheme uses
IR sensor and sigma delta ADC:
04/03/03 EDN-Design Ideas / Many noncontact
temperature-measurement systems use infrared
sensors, such as thermopiles, which can detect small
amounts of heat radiation. Biomedical thermometers
that measure the temperature of an ear or a temple
use noncontact temperature measurement, as do
automotive-HVAC systems that adjust temperature
zones based on the body temperature of passengers... |
Temperature Measurement Scheme uses
IR Sensor and Sigmadelta ADC:
04/03/03 EDN-Design Ideas / PDF contains multiple
circuits - scroll to find this circuit |
Temperature Monitor:
|
Temperature Regulator #2:
|
Temperature Sensor Circuit Provides
Dual Slope Output :
01/21/02 Electronic Design - Ideas for Design / The
excellent linearity of integrated-circuit
temperature sensors makes them ideal for direct
analog compensation of the thermally induced errors
inherent in many circuits. For example, a
negative-sloped temperature sensor could compensate
for an... |
Temperature Sensor Doesn't Discharge
Battery: 08/01/96 EDN-Design
Ideas |
Temperature Sensor uses I2C isolator:
06/05/96 EDN-Design Ideas |
Temperature Strip-Chart Recorder Uses
Parallel Port: 03/01/04
Electronic Design - Design Briefs / A simple,
inexpensive method for building a temperature
strip-chart recorder involves a parallel port that
communicates with four TMP121 IC temperature sensors
(Fig. 1). The sensors communicate via the. . . |
Temperature-Compensated LCD Bias
Supply Uses A Single Control IC:
06/08/98 Electronic Design - Ideas for Design / Many
applications require a simple method for getting
multiple outputs from the power supply. One way to
achieve this goal is by using charge pumps. The
schematic shown in Figure 1 is an LCD bias. . . |
Temperature-Sensor Circuit Provides
Dual-Slope Output:
01/21/02 Electronic Design - Ideas for Design / The
excellent linearity of integrated-circuit
temperature sensors makes them ideal for direct
analog compensation of the thermally induced errors
inherent in many circuits. For example, a
negative-sloped temperature sensor could compensate
for an. . . |
TempSentry Temperature Sensor
Technical Info & Schematics:
|
Thermistors and a Microcontroller
Simplify Anemometer Design
: 10/14/02 Electronic Design - Ideas
for Design / Typically, air flow is measured with a
hot-wire anemometer. Here's an alternative version
of that concept using two thin-film platinum
resistance temperature detectors. A high-performance
mixed-signal microcontroller can make the
measurement and drive... |
Thermocouple Interfaces to Serial
Port: 11/09/95 EDN-Design
Ideas |
Thermocouple thermometer features a
1-mV/�F output: 10/18/99
Electronic Design - Ideas for Design / An
inexpensive, battery-powered,
cold-junction-compensated, thermocouple thermometer
with an output of 1 mV/�F can be constructed using
type-K thermocouple wire. Because type-K
thermocouple. . . |
Thermoelectric Controller (scriptable
Thermometer): |
Thermostat For High-Altitude
Atmospheric Sampler is Fault-Tolerant:
11/19/01 Electronic Design - Ideas for Design /
Among the many measures of good circuit design
(e.g., cost, performance, and efficiency), none is
more important than reliability. Usually, adequate
expected reliability can be achieved by simply
sticking to conservative design rules and good. . . |
Thermostat Node Schematic:
|
Three Channel Spectrum Analyzer: |
Transistor Forms RS232C Digital
Thermometer: 05/09/96 EDN-Design
Ideas |
Transistors offer thermal protection
for controller:
07/19/2001 EDN - Design Ideas / When a switch-mode
power-supply controller, such as On Semiconductor's
NCP1200, operates at a high ambient temperature, you
should protect the entire power supply against
lethal thermal runaway. The NCP1200 operates
directly from the power mains without an auxiliary
winding; therefore, the die in the IC dissipates
power (Figure 1).. |
Two Chip Digital Thermometer Delivers
0.4�C Accuracy :
07/08/0Two Electronic Design - Ideas for Design / An
LED digital thermometer with an operating range
between 0�C and 150�C, 1�C resolution, and �0.4�C
accuracy is presented in the figure. This design is
based on the PIC16F872... |
Two-Chip Digital Thermometer Delivers
0.4�C Accuracy: 07/08/02
Electronic Design - Ideas for Design / An LED
digital thermometer with an operating range between
0�C and 150�C, 1�C resolution, and �0.4�C accuracy
is presented in the figure. This design is based on
the PIC16F872. . . |
Universal Programmable Remote:
|
USB Link Neatly Measures temperature:
10/26/00 EDN-Design Ideas / PDF contains multiple
circuits - scroll to find this circuit |
UV Sensitive Photodetector
: |
Varactor diode stabilizes temperature
for FM quadrature demodulator:
06/09/97 Electronic Design - Ideas for Design /
A quadrature detector is used to demodulate
frequency shift keying (FSK) and other types of FM
signals. The MC13156 shown is an FM subsystem
integrated circuit that downconverts the RF to a
10.7-MHz intermediate frequency (IF), amplification,
and. . . |
Webbased thermometer Project: |
ΔVBE-Based Cold-Junction Compensator
For Thermocouples:
11/06/00 Electronic Design - Ideas for Design / The
familiar thermocouple (TC) is probably the oldest
species of electronic temperature sensor extant. TCs
consist merely of two dissimilar conductors joined
at the temperature measuring point. They’re simple
to fabricate and look (at first glance) |