Analog Front-End. AFE4300 Datasheet
AFE4300 Low-Cost, Integrated Analog Front-End
for Weight-Scale and Body Composition Measurement
SBAS506 – AUGUST 2019
•1 Weight-scale front-end:
– Supports up to four load cell inputs
– On-chip load cell 1.7-V excitation voltage for
– 68-nVrms Input-Referred noise
(0.1 Hz to 2 Hz)
– Best-fit linearity: 0.01% of full-scale
– Weight-scale measurement : 540 µA
• Body composition front-end:
– Supports up to three tetra-polar complex
– 6-Bit, 1-MSPS sine-wave generation digital-to-
analog converter (DAC)
– 247.5-µArms, ±20% Excitation source
– 0.1-Ω Measurement RMS noise in 2-Hz BW
– Body composition measurement : 970 µA
• Analog-to-digital converter (ADC):
– 16 Bits, 860 SPS
– Supply current: 110 µA
Weight scales with body composition
The AFE4300 is a low-cost analog front-end
incorporating two separate signal chains: one chain
for weight-scale (WS) measurement and the other for
body composition measurement (BCM) analysis. A
16-bit, 860-SPS analog-to-digital converter (ADC) is
multiplexed between both chains. The weight
measurement chain includes an instrumentation
amplifier (INA) with the gain set by an external
resistor, followed by a 6-bit digital-to-analog converter
(DAC) for offset correction, and a circuit to drive the
external bridge/load cell with a fixed 1.7 V for
The AFE4300 can also measure body composition by
applying a sinusoidal current into the body. The
sinusoidal current is generated with an internal
pattern generator and a 6-bit, 1-MSPS DAC. A
voltage-to-current converter applies this sinusoidal
current into the body, between two terminals. The
voltage created across these two terminals as a
result of the impedance of the body is measured back
with a differential amplifier, rectified, and the
amplitude is extracted and measured by the 16-bit
The AFE4300 operates from 2 V to 3.6 V, is specified
from 0°C to +70°C, and is available in a LQFP-80
PART NUMBER PACKAGE
BODY SIZE (NOM)
12.00 mm × 12.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Functional Block Diagram
1.5k +/- 20%
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
SBAS506 – AUGUST 2019
4 Device and Documentation Support
4.1 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
4.2 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
4.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
5 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
2 Submit Documentation Feedback
Product Folder Links: AFE4300
Copyright © 2019, Texas Instruments Incorporated