Airflow Sensors
line Guide
Go with the flow of engineering leadership. All airflow sensors
operate on heat transfer — flow and differential pressure.
But Honeywell Sensing and Control (S&C) offers advanced
chip design, manufacturing techniques and microstructure
technology, allowing our microbridge to be notably faster, smaller
and more sensitive. Our silicon chip design is created from a thin-
film, thermally isolated bridge structure, containing both heater
FEATURES
HonEywEll ZEpHyR
oR DiGiTAl AiRFlow SEnSoRS
HAF Series-High Accuracy.
Features: i = competitive differentiator
i High accuracy • Full calibration and
temperature compensation
i Customizable i High sensitivity at very
low flows i High stability i Low pressure
i Linear output • Fast response time
• High 11-bit (analog) or 12-bit (digital)
resolution • Low 3.3 Vdc operating
voltage • Analog or ASIC-based I
output • Bidirectional flow • Insensitive to
mounting orientation and altitude • Small
size • RoHS compliant
Benefits: High ±2.5% accuracy allows
for very precise airflow measurement,
often ideal for demanding applications
with high accuracy requirements. Full
calibration and temperature compensation
typically allow customer to remove
additional components associated
with signal conditioning from the PCB,
reducing PCB size as well as costs
often associated with those components
(e.g., acquisition, inventory, assembly).
Customizable for specific end-user needs.
High sensitivity at very low flows allows a
™
AnAloG
2
C digital
customer’s application to detect presence
or absence of airflow. High stability
reduces errors due to thermal effects and
null shift to provide accurate readings
over time, often eliminating the need for
system calibration after PCB mount and
periodically over time. Low pressure
drop typically improves patient comfort in
medical applications, and reduces noise
and system wear on other components
such as motors and pumps. Linear output
provides more intuitive sensor signal than
the raw output of basic airflow sensors,
which can help reduce production
costs, design, and implementation time.
Fast response time allows a customer’s
application to respond quickly to airflow
change, important in critical medical
(i.e., anesthesia) and industrial (i.e., fume
hood) applications. High 11-bit (analog)
or 12-bit (digital) resolution increases
ability to sense small airflow changes,
allowing customers to more precisely
control their application. Low 3.3 Vdc
operating voltage option and low power
consumption allow for use in battery-
driven and other portable applications.
Analog output provides an interface for
and temperature sensing elements. This provides rapid response
to the air or gas flow and amount and direction, delivering
a proportional output voltage. Amplified versions provide
an enhanced output signal and less external circuitry, while
unamplified versions allow additional external circuit options.
What’s more, a variety of port styles provides greater application
flexibility.
reading airflow over the specified full
scale flow span and temperature. ASIC-
based I
eases integration to microprocessors or
microcontrollers, reducing PCB complexity
and component count. Bidirectional flow
sensing capability eliminates need for
two airflow sensors, helping to reduce
production costs and implementation
time. Insensitivity to mounting orientation
allows customer to position sensor in most
optimal point in the system, eliminating
concern for positional effects. Insensitivity
to altitude eliminates customer-
implemented altitude adjustments in the
system, easing integration and reducing
production costs by not having to
purchase additional sensors for altitude
adjustments. Small size occupies less
space on PCB, allowing easier fit and
potentially reducing production costs;
PCB size may also be reduced for easier
fit into space-constrained applications.
Potential medical applications include
anesthesia delivery machines, ventricular
assisted devices (heart pumps),
hospital diagnostics (spectrometry, gas
chromatography), nebulizers, oxygen
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C digital output compatibility
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