Texas Instruments Incorporated has unveiled the industryís first
family of fully integrated analog front ends (AFEs) for photometry.
The AFE44xx family integrates all the front end components
and associated timing control circuitry of a typical photometry
include clinical and home health pulse oximeters, photometry-based
blood glucose meters, and photoplethysmograph-based (PPG) heart rate
By incorporating fully programmable transmitter and receiver circuits
into one device, the AFE44xx family reduces end equipment manufacturersí
design time, board space and need for in-house analog design expertise
compared to discrete solutions. With less than 1-mA supply current, the
AFE44xx family consumes less power than discrete solutions, which
results in longer battery life. The AFE44xx family enables optimal
measurement performance, even in ambient light settings.
With its high level of integration and low power, the AFE44xx family
enables smaller, more portable traditional photometry solutions, as well
as the new emerging market of wireless
and smart connected pulse oximeter accessories. Available in the
AFE44xx family are the AFE4490, targeted at clinical applications; and
the AFE4400, targeted for home health applications.
The AFE44xx familyís receive path includes a programmable transimpedance
amplifier (TIA), ambient cancellation circuitry and analog-to-digital
converter (ADC). The transmit path incorporates the LED driver and
programmable 8-bit current source of up to 150 mA. With both transmit
and receive paths integrated into a single device, less time and board
space is required to design with the device.
The device family consumes less than 1 mA of power, to extend battery
life and offers open/short detection features make it easier for
engineers to diagnose system errors during design.
The AFE44xx family provides a flexible integrated timing controller
module that reduces the demands and overhead on system software.
Availability and Pricing
Both the AFE4490 and the AFE4400 are available now in a compact 6-mm x
6-mm, 40-pin QFN package. The AFE4490 is priced at $7.95 and the
AFE4400 is priced at $2.95 in quantities of 1,000.
Tools and support
Designers can immediately take advantage of the AFE4490 and AFE4400
evaluation modules (EVMs) which feature DB9 pulse oximeter sensor cable
support, include two modes of operation for evaluation and live SPO2 /
heart rate, and provide access to all the AFE44xx device registers via
an easy-to-use graphical user interface (GUI).
More information about the AFE44xx family and evaluation modules (EVMs) at www.ti.com/afe4400-pr and www.ti.com/afe4400evm-pr
This article originally appeared on EE Times Europe.