AFE159x Low-Power, 4-Channel, 24-Bit Analog Front-Ends for Bio-Potential Measurements

1 Features

Integrated Signal Chain for ECG, Pace Detection, and Respiration Measurement
ECG Receiver
- Four high resolution channels at low power of 0.42mW/channel
- Flexible four leads selectable from six electrodes
- Programmable gain: 1.25 to 9
- Input-referred noise: 4μV_PP in 150Hz BW
- Differential input range: ±1V with Gain = 4
- CMRR: -140dB
- Data rate: 125SPS to 128kSPS
Pace Detection
- On-chip digital pace detection algorithm on programmable two leads
- High-speed 128kSPS pace output on two channels for software pace detection
Respiration
- Low-noise of 24mΩ_PP with 2kΩ body impedance and 1kΩ defibrillator protection resistor on each electrode
- Supports Sine and Square wave excitation
Other Features
- Built-in right leg drive amplifier steerable to any electrode
- DC lead-off detection, AC lead impedance detection, Wilson Center Terminal (WCT), Goldberger Central Terminals (GCT), test signals
- Battery voltage monitoring
- Flexible power-down and standby modes
- Built-in oscillator, PLL, and reference
- 1k sample main FIFO and 2k sample pace FIFO
- SPI-compatible serial interface
- Analog supply voltage 1: 3.15V to 5.25V
- Analog supply voltage 2: 1.7V to 1.9V
- I/O supply voltage: 1.65V to 3.6V
Supports systems meeting AAMI EC11, AMI EC13, AMI EC38, IEC60601-1, IEC60601-2-25, IEC60601-2-27, and IEC60601-2-51 standards

2 Applications

Medical instrumentation (ECG, EMG, and EEG):
- Bedside patient monitoring and diagnostic ECG
- Portable telemetry
- Holter monitor and multi-lead patch
Event, stress, and vital sign monitors:
- ECGs
- AEDs
- Telemedicine Bispectral Index (BIS)
- Evoked Audio Potential (EAP)
- Sleep study monitor

3 Description

The AFE1594 is a family of multichannel, simultaneous sampling, 24-bit, delta-sigma (ΔΣ) analog-to-digital converters (ADCs) with built-in programmable gain Instrumentation Amplifiers (INAs), internal reference, and an on-chip PLL. The AFE supports digital pace pulse detection, thoracic impedance measurement and incorporates all of the features that are commonly required in medical electrocardiogram (ECG) and electroencephalogram (EEG) applications. Multiple AFE159x devices can be cascaded in high channel count systems. With high levels of integration and exceptional performance, the AFE159x enables the development of scalable medical instrumentation systems at significantly reduced size, power, and overall cost.

Package Information

PART NUMBER	PACKAGE⁽¹⁾	PACKAGE SIZE⁽²⁾
AFE1594	QFN	7mm × 7mm
AFE1593/AFE1594	WCSP	3.7mm × 3.7mm

(1) For all available packages, see Mechanical, Packaging, and Orderable Information.

(2) The package size (length × width) is a nominal value and includes pins, where applicable.

4 Device Comparison

Table 4-1 Comparison of the features between the AFE159x variants

	AFE159RP3	AFE159RP4	AFE159P4	AFE1594
Number of ECG electrode pins	6	6	6	6
Number of ECG channels	3	4	4	4
Number of Respiration electrode pins	4	3/4⁽¹⁾	3/4⁽¹⁾⁽²⁾	3/4⁽¹⁾⁽²⁾
Number of Respiration receiver channel	1	1	-	-
Number of internal Pace detect channels	1	2	2	-

(1) 4 electrodes supported in WCSP package.

(2) Only RESP_OUT pins available, RESP_IN pins are NC.

5 Device and Documentation Support

TI offers an extensive line of development tools. Tools and software to evaluate the performance of the device, generate code, and develop solutions are listed below.

5.1 Receiving Notification of Documentation Updates

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5.2 Support Resources

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5.3 Trademarks

TI E2E™ is a trademark of Texas Instruments.

All trademarks are the property of their respective owners.

5.4 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.

5.5 Glossary

TI Glossary

This glossary lists and explains terms, acronyms, and definitions.

6 Revision History

Changes from Revision * (June 2024) to Revision A (July 2024)

Updated device status to Production DataGo

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